statistical failure analysis of copper beryllium strip

Lehigh UniversityLehigh Preserve

Theses and Dissertations

1994

Statistical failure analysis of copper beryllium stripmetal springs using a new fatigue test methodW. Drew PeregrimLehigh University

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·AUTHOR:

Peregrim, W. Drew

TITLE:i

Statistical Failure Analysis

of Copper Beryllium Strip

Metal Springs Using a New

Fatigue Test Method

DATE: May 29,1994

STATISTICAL FAaURE ANALYSIS OF COPPER

BERYLLIUM STRlP METAL SPRINGS USING A

NEW FATIGUE lEST METHOD

by

W. Drew Peregrim

A Thesis

Presented to the Graduate Committee

of Lehigh University

-I"in Candidacy for the Degree of

Master of Science

III

Materials Science and Engineering

This thesis dedicated to Professor John Wood

John became a friend when we worked on a pr<;>ject together and convinced me to

pursue my Masters Degree.

III

Vita

W. Drew Peregrim was born the 11th of March 1957 to Walter and Jeanne

Peregrim of Scranton, Pennsylvania. He graduated from Wilkes University with a

Bachelor of Science degree in Materials Engineering while working full time as a

Design Engineer for the Babcock and Wilcox Co. After graduation he held the

position of Managing Technical Editor for Applied Science with the Northeast

Educational Institute.

Drew presently works for Instrument Specialties Co. 'as Technical Projects

Manager and is the owner of WAP Consuiting which specializes in structural

analysis of machine components using Finite Element Analysis. At Instrument

Specialties Co. Drew is in charge of new product development. Drew holds one

patent on an electromagnetic shielding device, with a'second patent pending. Drew

is active in many professional societies including ASTM where he is the chairman

<of the Electromagnetic Shielding Committee, and ASMI where he sat on the local

chapters steering committee. He is also a member of SAE, NACE, and the

Electrochemical Society where he is active in presenting technical papers and writing

technical standards in corrosion control and electromagnetic shielding.

Drew resides in Bear Creek, Pennsylvania with his wife Kathyleen and two

children Christine and Adam.

IV

Table of Contents

Results and Discussion

Appendix A

Alloy 17200 1I4HT

Alloy 17200 XHM (190)

Alloy 17410

'AppendixE

Alloy 17200 (Failure Distributions)

Abstract

Introduction

Procedure

Conclusions

References

Alloy 17200 HT

Page 1

Page 3

Page 13

Page 18

Page 58

Page 63

Page 64

Page 65

Page 90

Page 100

Page 107

Page 116

Page 117

v

ABSTRACT

An industry developed method for testing cycle life of strip metal springs was

used to produce metal fatigue data in quantities large enough for detailed statistical

analysis. This cycle life test method is called Endurance Testing and is described in

detail. The fatigue data was analyzed using advanced statistical techniques and

computerized stress analysis. After the analysis was complete, the results were

compared to standard fatigue testing on the same lot of material using the ASTM

B593-85 test method.

The main advantages ofthe "Endurance Test method" are easily machine test

samples and the ability to simultaneously test up to 48 fatigue specimens at a time.\

Testing 48 specimens simultaneously w~s used to advant~~oducing enough test

data points to analyze statistically. Several statistical distribution functions were

tried, with a close match found between the fatigue test data and a three parameter+-

Weibulldistribution of the log of cycles to failure. Other commonly used statistical

distributions used for analyzing fatigue test results such as the two parameter

Weibull distribution are shown to provide a poor correlation to the metal fatigue

data.

Also discussed in this thesis is the ability of computerized Finite Element

Analysis to accurately analysis the complex stress distribution in a formed strip

Page 1

metal spring. This is verified by comparing the fatigue data from ASTM testing to

endurance test data. The maximum stress on the endurance test specimens were

predicted by Finite Element Analysis while the stress on the ASTM fatigue specimens

was extrapolated from strain gauge measurements.

Page 2

./

INTRODUCTION

1.0 BACKGROUND

About 30 :years ago Instrument Specialties Co. (I.S.) received several requests for

<::::metal fatigue data on Beryllium Copper strip springs. In response to this Instrument

Specialties Company invented and built a fatigue testing apparatus which Instrument

Specialties Company called the "Endurance Test Machine"l. The machine consisted of two

rows of 24 fatigue test specimen holders, allowing up to 48 fatigue specimens (Figure 1.0-1)

to be tested simultaneously. The machine is a constant deflection test machine with each

bank of 24 specimens tested to the same deflection.

The original "Endurance Test" specimen was a rectangular strip ofmetal.378 inches

wide, and 2 inches long. All the specimens in each bank of 24 were deflected the same

amount by a set of pins connected to a moving rail, one rail for each of the two rows of

specimen holders. These rails or contact pin holders are shown in Figures 1.0-2, and 1.0-3.

Each of the pins that contacts the specimens were connected electrically to an hour meter.

When each specimen broke, the connection was broken and the individual hour meter

stopped.

An electric motor with a speed control drives an adjustable crankshaft which moves

the rails with a back and forth movement The adjustable crankshaft is shown in Figure

1.0-4 and is labeled 1. This adjustable crankshaft produces the fine adjustment for setting

Page 3

the specimen deflection. Multiplying the time in minutes recorded on the hour meter, after

a fatigue specimen failed, by the RPM of the motor gave the cycles to failure.

In preliminary tests comparing commercially produced contact springs,· the

"Endurance Test" data proved to overestimate the fatigue life of the springs. It was

determined that the typical configuration of a contact spring induced a stress concentration

because of the sharp bend usually found in the high stress region. The "Endurance Test"

specimen configuration was changed from a straight specimen, to a specimen with a tight

45 degree bend at the high stress region. See Figure 1.0-1.

This specimen shape closely matched the shape of typical contact springs. These

springs typically have a flat portion which provides for mounting. The spring usually has

a tight bend and a straight portion which extends from this bend and forms the spring arm.

The electrical contact and source ofthe springs deflection is usually at the end of this spring

arm. The new specimen duplicated the stress concentrations of typical springs and

provided a superior correlation between actual spring life and metal fatigue testing.

After producing some promising data, the hour meters of the original machine began

to fail. Replacement parts were difficult to obtain, and the test program was abandoned

until 1986 when the test program was revived due to a renewed interest among Instrument

Specialties Company's customers. Several new contact alloys were coming on the market,

and comparison data on these alloys was needed.

Page 4

The "Endurance Test" machine was rebuilt using an electronic control system to

replace the ~nreliable hour meters. The control system determined if an endurance

specimen failed by measuring continuity across the specimen. Figure 1.0-2 shows the

arrangement of test specimens in the Endurance Tester including how the contact pin

deflects the specimen. The specimen holder or mounting' fIxture (item 3 -in Figures 1.0-2

and 1.0-3) anchors the specimen to the test machine. Figures 1.0-3 and 1.0-4 show the

endurance test machine.

The contact pin holder (item 2 in Figures 1.0-2 and 1.0-3) moves parallel to the block

holding the specimen mounting fIxtures. The movement is controlled by the adjustable

crankshaft, and linkage arms shown in Figures 1.0-3 and 1.0-4. The deflection can be

adjusted coarsely by attaching the lead control arm to different holes along the fIrst link

arm (item 2 of Figure 1.0-4). The fIne adjustment is made by sliding the end link in and

out in aT-slot on the crankshaft (Item 1 in Figure 1.0-4).

Each of the linkage rods has left and right hand threads so that their lengths can be

adjusted by rotating the linkage rod. This allows fIne adjustment of the contact pin holders

position. The ratio of deflection of the two contact pin holders can be varied by moving the

rod end to different holes in the linkage arm (Item 3 of Figure 1.0-4). This allows different

deflections to occur in the two contact pin holders, and so deflect the specimens different

amounts· in each bank of the "Endurance Test" machine. 1\\'0 different stress levels can

be tested simultaneously in the machine by adjusting this deflection ratio.

Page 5

When the specimen failed, electrical continuity was broken, and the control system

would indicate which specimen failed and shut the machine off. With the machine shut

down, each specimen that failed can be vismtlly verified before continuing the test. This

eliminated any. false alarms which would happen due to corrosion and abrasion of the

"Endurance Test Specimen" between the specimen and the contact pin.

To give credibility to the comparison of fatigue test data of different connector alloys

using the "Endurance Test" method, it was decided to first compare "Endurance Test"

results to ASTM B593-852 test results. To insure a good comparison, material from the

same coil of metal was used in both studies. Brush Wellman Incorporated3 provided the

test material, and performed the fatigue testing using the ASTM method at their facility.

This test data was used as a point of comparison to verifY the results of "Endurance Test"

results.

Four of the most common conductive strip metals based on Beryllium Copper were

chosen for this test program. These materials and some of their properties are described

in Table 1.0-1. The first three materials are variations of the same alloy C17200. Two of

these materials (C17200 1/4H and C17200 H) are differenqated by the amount of cold

rolling (temper) before ·ageing. The third material C17200 XHM (commercially known as

Alloy 190 XHM) is rolled and heat treated as received. No heat treatment is required after

forming with Alloy 190.

Page 6

Springs made from alloy 17200 1/4HT and 17200 HT are both formed in the solution

annealed condition and are later subjected to a ,solution ageing heat treatment. This final

heat 'treatment removes most of the residual forming stresses in these 'materials. These

three variations of alloy C17200 have different strengths, and in the case of alloy 190

include residual forming stresses not relieved by a final heat treatment. The last material

"Alloy 17410" is a relatively new alloy which is becoming increasingly popular in industry.

Alloy 17410 was chosen because it is also a Copper Beryllium alloy" and no metal fatigue

data is currently available on this alloy

Page 7

'S".cos.----- .ass 'e

.I(.,'C,

_.001

.0''0 DIP-..

t+---+--- .I '0'0..---l--*--:~:;,c.,*.oo't.

Endurance Test SpecimenFICURE 1.0-1

Page 8

-...:;n~

-a I I

~

-.7

~I~I

r-.-110

0'1 "0'1

1. Mounted Endurance Test Specimens2. Moving Contact pin Holder

3. Specimen Mounting fixture

Endurance Test Machine - Test SetupFIGURE 1.0-2

----

1. Mounted Endurance Test Specimens2. Moving contact Pin Holder

3. specimen Mounting fixture4. Adjustable Control Rod

...... In .... ".. Test ne

CURE 1 ..0 ..3

1. Fine Deflection Adjustment2. Coarse Deflection Adjustment

uI

3. Deflection Ratio Adjustment

..

Properties of Beryllium Copper Alloys

ppy

CI7200 1I4HT CI7200 HT C17200 XHM C17410

(190 XHM)

Heat Treatment 2 Hours@ 2 Hours@ Proprietary Proprietary

600'" 6OOF' from Supplier from Supplier,

Tensile Strength 175 to 205 KSf 190 to 220 KSf 155 to 175 KSf 110 to 130 KSf

Yield Strength .2% • 159.8 KSf 196 KSf 140 KSf 112.5 KSf-

Elongation %/

3 to 10 1 to 6 4 to 15 7 to 17

Hardness DPH 353 to 424 373 to 446 1317 to 378 210 to 278-- ~ ----

Electrical 22 to 28 22 to 28 17 to 28 45 to 55

Conductivity--

% lACS -

CHEMICAL

COMPOSITION - %

Beryllium 1.80 - 2.00 'i.80 - 2.00 1.80 - 2.00 0.15 - 0.50---- -- \ - ------ -----------

Cobalt - - - 0.35 - 0.60

Cobalt + Nickel 0.20 min 0.20 min 0.20 min -

Cobalt + Nickel + .06 max .06 max .06 max -Iron

Copper Balance Balance Balance Balance

Ph'sicaJ arameter --tal< enotrotLmaterial certification ~other arametersllFe f rom material -

suppliers catalog

Page 12

. Ii'

PROCEDURE

-;1.1 FATIGUE SPECIMEN PREPARATION

The I.S. '''Endurance Test" specimens were blanked in a stamping die with

tight clearances to produce a minimum burr size. A hole was then pierced in the,

center, of one end. This hole was precisely located and is used to align the specime_n

in the bending die. Details of the I.S. "Endurance Test" specimen are shown in-

Figure 1.0-1. This hole is also used later to align the specimens in the load gauge.

The 45 degree bend is then formed in a wiping die with the burr on the outside of

the bend (compression side of specimen as tested.) Specimens not requiring heat

treatment such as mill hard alloys are degreased, and are then ready for load

measurement.

Specimens requiring heat treatment (Alloys 17200 1I4H and 17200 II) were

placed in a heat treat fIxture. The fIxture clamps and holds the specimen so that it

retains its shape during the heat treat process. The fIxture used allows the heat

treatment of 12 specimens at a time. The specimens remain in the fIXture until the

heat treatment is completed and the fIxture is cooled to room temperature.

-

A liquid salt bath was preheated to the heat treat temperature recommended

by the manufacture of each alloy. The loaded fIXture was then immersed in the

liquid salt for the time period recommended by the manufacturer. Upon removal

Page 13

from the liquid salt the loaded fIxture is quenched in water. ~This quickly cools down

the fIxture and also helps dissolve the salt which entrusts the specimen. The

specimens were then removed from the heat treat fIxture.

The liquid salt heat treatment leaves a light layer of scale on the fatigue test

specimens. This scale was removed by dipping the parts in a series of caustic

chemical baths. For cleaning Beryllium Copper the commercial procedure is called

"Bright Oean" and consists of the following dips. The exact concentrations of these

chemicals are proprietary to Instrument Specialties COl.

1. Alkaline Oeaner - concentrated alkaline bath

2. Sulfuric Acid Pickle - Concentrated hot sulfuric acid mixture

3. Sulfuric/Peroxide Desmut - Concentrated mixture of sulfuric acid and

hydrogen peroxide

4. Copper Shield Anti-Tarnishing Solution - BTA solution

5. Vapor Drying - Hot Vapor Degrease with Trichloroethylene

Some Beryllium Copper alloy specimens were processed through a

proprietary cleaning process called' 'Endurance Finishingl". "Endurance Finishing"

is a tumbling operatioIiwhich fInely polishes the specimens while removing burrs.

The test results of "Endurance Finished" test specimens were treated separately in

this investigation so as to determine if the "Endurance Finish" process actually

Page 14

improves the fatigue life of contact springs.

1.2 LOAD DEFLECTION MEASUREMENTS

The width, thickness, and "A" dimension of the finished "Endurance Test"

specimens was then measured. The "A" dimension is shown in Figure 1.2-1. The

"A" dimension is a measurement of the "Endurance Test" specimen which

determines the distance from a fixed point on the "Endurance Test" specimen as

mountedin the "Endurance Test" machine to the point of contact at zero deflection

of the contact pin. This provides a reference point for setting up the test machine.

The mean of the "A" dimensions of a test group is then calculated. The

specimen with the "A" dimension closest to the mean "A" dimension is made the

master specimen and is used to set up the test machine.

Using the simple deflected beam formula, Equation 1.2-1, the load ,F, at the

contact pin necessary to produce the desired maximum stress "ef' is calculated.

a Wt 2F =

6L

EQUATION 1.2-1

Where: F = Load required to produce the desired maximum stress

Page 15

·w = Width of specimen

t = Thickness of specimen

L = Vertical distance from clamp to contact pin

The master specimen is then placed in a test jig which is a duplicate of a

specimen holder from the "Endurance Test" machine. The contact pin of the test

jig is connected to a load cell which measures the contact force of the deflected

"Endurance Test". specimen. A micrometer deflects the specimen until the

calculated force (F) of Equation 1.2-1 is reached.

The deflection is recorded, and each specimen in tum is placed in the test jig,

and deflected the same amount. The load on each specimen is recorded. Since the

"Endurance Test" machine deflects each specimen in a test group the same amount,

the stress on each specimen during the test can be calculated from the previously

measured values. The procedure for this is given in section 2.1.

Next the specimens are mounted in the "Endurance Test" machine and the

machine set to deflect the specimens the same amount as was measured above. The

"Endurance Test" machine is started, and the cycles to failure of each specimen is

recorded. The frequency of the "Endurance Test" machine is adjustable from 500

cycles per minute to about 2000 cycles per minute. A standard frequency of 1000

cycles per minute was used throughout the test program.

Page 16

A DiMension

0,9999/1

Endurance Test Specimen - "A" DimensionFIGURE 1.2-1

RESULTS AND DISCUSSION

2.1 ANALYSIS OF SPECIMEN STRESS

The stress on each specimen was determined by first measuring the load on

a fully deflected specimen. The length, width, and thickness of the specimen along

with the load on the specimen was used to calculate the load on each specimen

before the test start. The simple deflected beam relationship of Equation 2.1-1 was

at first used to calculate the stress on each "Endurance Test" specimen.

F*L*6a=---W*t 2

EQUATION 2.1-1

Where: (j = the maximum stress

W = width of specimen

L = length of specimen

t = thickness of specimen

F = force

This simple relationship along with the shape of the "Endurance Test"

specimen correlated well to cycles to failure of contact springs whose stress was

Page 18

calculated in a similar manner. The ASTM specimen's2 stress was determined from

strain gauges mounted to the specimens. The ASTM fatigue test resulJ indicated'. ~

significantly longer fatigue life at the same stress level as the "End~e Test"

specimens. This indicated that the cantilever beam method of calculating the stress

on "Endurance Test" specimens was not accurate, and the actual stress was

significantly greater than that calculated.

Instrument Specialties Company started using Finite Element Analysis

software called NISA n4 to accurately predict stress in a deflected spring. Finite

Element Analysis (FEA), has been used for many years to design critical,components

for spacecraft, aircraft, automobiles, etc. An FEA model of the loaded "Endurance

Test" specimen was made, and analyzed on a computer. The stress pattern on the

"Endurance Test" specimen as analyzed using NISA n is shown in Figures 2.l-lA

and 2.l-lB. These figures show the right half of the specimen. A mirror image of

the stress distribution occurs on the left hand side. Figure 2.2-1A shows the stress

distribution on the bottom or tension side, while Figure 2.2-1B shows the stress

distribution on the top or compression side.

From this figure you can see that there are three significant stress

concentration areas on the bend area of the "Endurance Test" specimen, the center,

and a region near the edge on either side. In examining the failed "Endurance Test"

specimens, the fracture always started at one of these three stress concentrations,

Page 19

and then continued toward one of the other high stress regions. The difference

between calculated stress and FEA stress is shown in the raw test data iIi Appendix

A for each specimen. This difference averaged about 10 KSI (68.9 MPa) higher for

the stress levels tested. This proved to explain most of the difference between the

ASTM fatigue test results, and the beam formula calculated "Endurance Test"

results.

The stress value used in the final analysis of the fatigue data was the mean

FEA stress of a test group. Since each specimen in a test group experiences the

same deflection, and not the same stress, a narrow distribution of stresses occurs for

each test group. The mean and standard deviation stress of each test group is shown

in Figures 2.1-2 to 2.1-5.. The standard deviation of stress for a test group was...

usually under 4 KSI (27.6 MPa), except where the stress exceeded the 0.2% yield

strength for. individual specimens. The stress variability within each test group is

small enough that the entire group can be considered at the same stress for statistical

analysis of the cycles to failure data. This narrow range of stress distribution also

shows that the "Endurance Test Specimens" tested are very consistent in shape and

thickness.

2.2 WEffiULL STATISTICAL DISTRIBUTION

Initial examination of data from "Endurance Testing" showed that early in

a test the frequency of failures would increase very quickly to a peak value, and then

Page 20

<. decrease slowly until the end of the test The pattern of these failures resembled a

normal distribution which was not symmetrical, and was skewed toward the high

cycle life side. To analyze the "Endurance Test" data a two parameter Weibulld"

distribution function was chosen. The second parameter of the Weibull function is

a shape parameter, which alters the shape of the statistical distribution and controls

the amount of skew in the statistical model. The Weibull cumulative distribution

function is given in Equation 2.2-1 5,6.

F(n) = 1 - e -(~)P

EQUATION 2.2-1

Where: a = Weibull Scale Parameter

~ =Weibull Shape Parameter

n = Number of cycles to failure

F(n) = The probability of failure at a given n

The alpha and beta parameters are determined from each group of test data

using the following equations. The degree of fit equation is given in

Equation 2.2_25,6. When the alpha and beta parameters represent the best fit to the

data, D(J3) equals zero. The maximum likelihood estimate of alpha is given by

Equation 2.2-2.

Page 21

1 N [(X)P] 1D(p)=-Eln(xi) --.i -1 --N i=l a P

EQUATION 2.2-2

Where:

EQUATION 2.2-3

EQUATION 2.2-4

N = Number of Test Pieces in a Test Group

Xi = The Cycles to Failure of Each Test Specimen in a Test Group

e = Natural exponent

The technique to finding the scale and shape is an iterative technique. The

above equations were programmed into a Quattro Pro spreadsheee, and the Alpha

and Beta parameters for each test group were calculated to a tolerance of 10-8.

Page 22

The resulting Weibull distribution was plotted against the actual test points

for each test, and is shown in Figures 2.2-1 through 2.2-12. The cumulative

distribution 5, 6 is given by

-(X-Xe)'P (P-l).

(P) = - (X-Xo> eP .

cz

EQUATION 2.2-5

Where:

(P) = The probability of failure

x = Cycles to Failure

Xo = Threshold Value (0 for 2 Parameter Weibull)

(Xo is also commonly referred to by the symbol "y")

The Quattro Pro spreadsheet allowed preliminary analysis of the data, and

helped prove that the two parameter Weibull statistical distribution did not properly

characterize the fatigue data. The two parameter Weibull function predicts that a

significant number of failures will occur at low fatigue cycles. This is not indicated

by the test data especially at low stress levels.

The distribution of the test data is shown in the graphs in Appendix B. The

region between the first failure, and the last failure was segmented into 10

sub-regions. The number of failures that occurred in each sub-region is shown by

Page 23

the height of the bars in the graphs. This is the two parameter Weibull data that

is plotted in Figures 2.2-1 to 2.2-12 as the actual distribution from the test results.

A three parameter Weibull distribution was tried next. The three parameter

Weibull cumulative distribution function is given by Equation 2.2-5 5,6. The Weibull

threshold parameter is the number which is subtracted from each cycle to failure

value before the two parameter Weibull function is calculated. After the Weibull

distribution is found, the threshold value is then added to the distribution creating

an offset value for the zero probability of failure. Th~ probability of failure is

mathematically zero at the threshold value, and by dermition is zero below the

threshold value.

Like the a and ~ parameters, the Weibull thresholtvaIue (y) is determined

using an iterative technique. The threshold value is determined when a log plot of

percent failures vs cycles to failure best matches a straight line. The shape of this

plot is manipulated by offsetting the data by a trial threshold-;11ue. To determine~

the best fit to a straight line, the following equation is used.

EQUATION 2.2-6

Page 24

Where:

M=

ELog(Xi-yt) * ELn(N%)

N

[Log(Xi-y t)]2

N

- E [Log(Xi - Yt) * (Ln(N% )]

- E [Log(Xi- Yt)]2

EQUATION 2.2-7

N% = The number of failures which have occurred up to and including

the test point divided by the total number of test points.

Xi = The cycles to failure of a test point.

Yt = The Weibull trial threshold value.

N = The number of specimens in a test group

The trial threshold value equals the true threshold value when R of Equation

2.2-6 is maximized. Equation 2.2-6 is the least squares degree of fit equation

modified to work with the X and Y axis of a Weibull distribution plot. When the

Weibull threshold value Yis determined for a test group, each Xi point is then

reduced by the threshold value y. The Weibull a and ~ parameters are then

determined from the modified Xi data just as they were for the two parameter

Weibull distribution.

The three parameter Weibull distribution is also plotted in Figures 2.2-1

Page 25

through 2.2-12 using the same evenly distributed points. Although the three

parameter Weibull distribution shows a bettercorrelation to the actual test data

than the two parameter Weibull distribution, it was not a good match. This

indicated that either the data is random, or a different mathematical technique was

needed.

In examining the correlation of the three parameter Weibull distribution to ~

the actual failure distribution (Figures 2.2-1 to 2.2-12), it was noticed that the three

parameter distribution peaked earlier than the test data indicated, and that the three

parameter distribution was also wider than the actual data. The test data could not

be normalized by the three parameter Weibull distribution alone. Fatigue data is

commonly plotted on a log scale, and the crack growth rates predicted by fracture

mechanics are also logarithmic in nature. With this in mind, the three parameter

Weibull analysis on the log of the cycles to failure was the next distribution to be

evaluated.

The three parameter Weibull analysis procedure using the log of the cycles

to failure was used to determine the Weibull constants for each "Endurance Test"

of alloy 17200 1/4R The antilog of this probability distribution was then plotted in

Figures 2.2-1 through 2.2-12 and compared with the other statistical techniques. The

three parameter Weibull distribution of the log of the fatigue data provided the

closest match to the actual fatigue failure distribution of the three distributions tried.

Page 26

.,

All the "Endurance Test" data was finally analyzed using the three parameter

Weibull analysis on the log of cycles to failure.

2.3 COMPARISON TO ASTM TEST RESULTS

Researchers at Brush Wellman Inc.3 used material from the same coil of

metal and performed ASTM metal fatigue testing. The Brush Wellman produced

ASTM test results were compared to the 500AJ failure prediction of the "Endurance

Test" data. The 500/0 failure point was predicted using the three parameter Weibull

technique using the log of cycles to failure. The results of the comparison is shown

in Figures 2.3-1 to 2.3-4. The ASTM results plotted are individual specimen failures

because there was not enough test data to attempt a statistical analysis. The ASTM

tester tests only 1 specimen, and Brush Wellman had access to three testers. With

the ability to test only three specimens at a time, Brush Wellman could not produce

enough data to permit a detailed statistical analysis.

The "Endurance Test" machines ability to test many ,specimens

simultaneously was used to advantage to gain a significant statistical test group. At

high stresses, where the failure distribution is relatively tight, the test group size

usually consisted of 12 specimens. As the fatigue limit of the alloy was approached,

the scatter in the failures increased dramatically. The number of specimens in a test

group was increased to 48 when the fatigue limit was approached, or the scatter

increased. This was not possible with the ASTM test method, due to the limitation

Page 27

on the number of specimens which could be tested.

The "Endurance Test" results were broken down into two categories for each

alloy and temper. "Endurance Finished" fatigue results are identified separately

from the standard manufactured finish (bright clean for heat treated alloys, and the

mill finish for mill hard materials). Most of the "Endurance Test" results are

comparable to the ASTM test results with some "Endurance Finished" test groups,

showing a trend toward early failures. In general the "Endurance Finished"

specimens produced more repeatable data, and a better correlation to the ASTM test

results than standard finished parts. This indicates that there is a source of

variability in the contact spring manufacturing process (the same manufacturing

processes used to make the "Endurance Test" specimens is used to make precision

springs), and that this can result in reduced fatigue life. The "Endurance Finishing"

process lessens this variability, but does not eliminate it.

The "Endurance Test" specimen undergoes all the manufacturing operations

of a manufactured spring, and the variability in the results mimics the problems seen

in production springs. These problems were usually blamed on a bad lot of material.

The test results indicate that the variability is more likely due to a variability in the

manufacture of the springs. The test results varied batch to batch from the same

coil of material. During the test program, the specimens were blanked in a large

batch, with specimens randomly selected from the bulk for each test. The specimens

Page 28

were then formed into the "Endurance Test" specimen just before each test This

should have randomized any variability in the coil.

2.4 TREND OF THE WEffiULL PARAMETERS

The large quantity of test groups analyzed for Alloy 17200 1I4HT allowed

analysis of the trend of the Weibull parameters. The individual Weibull parameters

from each test group were plotted against the stress of the individual test groups.

These graphs are shown as Figures 2.4-1 to 2.4-3. A least squares line fit was

performed on this graph and the results presented. Several test points were

eliminated from each least squares line fit because they fell well outside the trend of

the majority of the data. These points were so far removed from the majority of the

test points that the line fit including these points fell outside of the bulk of the data.

Using the linear relationships developed from each ofthe Weibull parameters,

a relationship was developed which related the trend of the Weibull parameters to

cycles to failure. Multiple plots were developed using the Weibull probability density

function to predict the 1010, 10%, 50%, and 90% failure points at different stress

levels. These plots are shown in Figure 2.4-4. The predictions are not unreasonable

and results in a detailed description of the fatigue behavior of alloy 17200 1I4HT

between the 0.2% Yield' Strength, and the fatigue limit of the material.

Unfortunately this plot required the results of over a thousand individual test points.

Page 29

This is only possible because of the ability of the "Endurance Test" machine to test

so many specimen~ at a time.

2.5 HUMIDITY EFFECfS

Humidity was not controlled during the major portion of the "Endurance

Testing" program. This was thought to be a possible cause of variability in the test

results, and so was investigated. Ambient humidity was not measured during the

test program, and so to determine any humidity effects, the relative humidity as

recorded by the local U.S. weather service was obtained and compared to the test.;

results. No correlation to the variability of the test results was noted in this

comparison. To further confirm that the variability in test results was not due to

humidity, the last tests were performed in a sealed tester packed with activated .

desiccant There was no improvement in consistency with the dry environment.

2.6 FATIGUE TEST RESULTS ON ALWY 17200

The fatigue test results on alloys 17200 1/4HT and HT were similar in shape,

with the stronger HT material producing about the same fatigue life with a 20 KSI

increase in stress. This is shown in Figures 2.3-1 and 2.3-2. These alloys are

chemically identical, and are differentiated only by the amount of cold reduction

after the final solution annealing. The difference in the .2%, yield strength for these

alloys is 36 KSI, and the difference in the fatigue results represented about half of

the difference in the .2% yield strengths.

Page 30

The fatigue life of the mill hard version of alloy 17200, the XHM temper,

produced significantly lower fatigue life than the HT materials. The fatigue test

results are shown in Figure 2.3-3. The.20./0 yield strength of alloy 17200 XHM is

lower than that of the 1/4HT and HT versions of this alloy which partially explains

the difference in fatigue life. This can also be explained by the presence of residual

forming stresses in the mill hard material. The 1I4HT and HT materials are solution

aged after forming which removes most of the forming stresses. Specific material

properties for the materials tested are given in Table 1.0-1

2.7 FATIGUE LIFE OF ALWY 17410

Alloy 17410 is also a Copper Beryllium alloy, but has a different chemistry

and metallurgy than alloy 17200. This is a special alloy with lower strength than

conventional Copper Beryllium alloys, but with higher conductivity. It is also only

available as a mill hard alloy, and includes residual forming stresses in the finished

"Endurance Test" specimen. This data is shown in Figure 2.3-4. The specific

material properties for this alloy are given in Table 1.0-1

Page 31

FIGURE 2.1-1A

-:t'r.~

'.;;t ....

E.M.R.C. - DISPUl't-II POST-PROCESSOR IJER 2-.'30

I

EHOURAHCE TEST SPECIMEN - TENSIOH SIDERIGHT HAL, OF TEST SPECIMEN

Hay/HV1993 STRESS COHTOURSUOH-HI SES STRESS K S JUIE~ : 9.~3E.Q4

RAHCE : L 19EH~S

(Band * 1. QE3)~ 119.4..,

6 112. a

S lIi~6 . 3

4. 99.7Q

3 93.13

_2_ 86.57

Min 8Q.QQ

,'1 IX RX= 22\ RIf= 6Q\ RZ= 2:>'------.....2

Stress Distribution - Tension Side

:;,""'r.;':;

'.;0',M

E.M.R.C. - D!~PL~V-II POST-PROCESSOR VER 2.30

ENDURAHCE TEST SPECIMEH - (OMPRESSIQH SIDERIGHT H~Lf 0f TrST SPfCIMfN

Mily/llV1993 STRESS CONTOURSIJOH-HISES STRESS K S IIJJEY : 7.48E.Q4RilHGF.: : 1.12[.Q5

<Band * 1.~[3)

~~ 112.1

FIGURE 2.1-1B

Stress Distribution - Compression Side

,~e

en~

I

enen

~ (J):;1-n .....-:: en

'4-'<:(...wu..

ALLOY 17200 1/4HT

':~~-----~----~--~---"~----r--10.2% YIELD STRENGTH I[~~I"~~~--- . " ! "i" i 1

:~~= -=- -'. -.:_---~~~-" ----~: --..~.-; -----~=~- ... .~.l~==I= ~~=I! CB-l ! : \ I

.. 4 s-; .. - --:-.--.;----.....-.---. --..... ---- ..-..----- -.-- .-~- ...--,~--~-!--~~-!

~ 4!j-"---- . .-~--...-- ;--....--.--.. ---.... --..--..---.-~ .. --- .--.....~.-.~~-,~~~-

i : I ! I

,35"'---~;--- A:----~\~-----. ---- ...--..--.....~--.- ..-------.! F/J·1! , I

~ -'0-+-~-.. :.--+-..--.... -----;. -----.----..-----.~-~ ..~---~ ! • 40·2 • !

..2sL~-A:t~-·--72-1 ,----i 175% OF 0.2% YIELD STRENGTH~rf I, • I I

'<:cr; 58'1 •

< : s-i-rXY'lJj~.,.n-t; rr IB,.. Jt-----.---·-·----A2'1---·-- i----·-,----;-------_._--_.

.,..... . . ' , , .

<C5--~~2____--, .'---'--- ~~-..---'----..-:-.------.--" ~<' ! !

.. Cr,-----W-'-- -~--------~--~ ----~.----:-.._-------_._---7'4,- " '. 4 Q-i, !

j5------·-~LG1.L--.-----,-------,---T--- .._-----------1

"..... 75-1! ,j J- .-.....- .. -_.. " '-~-'- •.----..-------...---' .---,------.-.-._,

, !

;;S-'-·---·----- --' ---"---T-- 50% OF 1).2Ok YIELD STRENGTH I:;.r: i I I iIi I I

" 2 4 5 8 10 12 14 16

Standard Deviation - KSI

•Bright Clean....

Endurance Finish I

VARIABILITY OF STRESS IN ENDURANCE TESTING

FIGURE 2.1-2

ALLOY 17200 HT

11III

Bright Clean

•Endurance Finish

14-4.6..

---_._-_..-,_.-----_._-_._~ - -_._...._---'--.-.- ---- ,--------------------_._-----_.-11

12Q--'----~ ..------ ~ - -. - -- -- --

122 i 64-1 Ii 11III I

1--' !! 11 1. !

!115+11III---

~ i 4-~en~ 11

- ---_.__..

" _ ----')- , -,----- - ..- .-.1I);oJ ')~v : _

18- _'._,1061-

CIJ < • 0 iCIJ " --:~~- -~ .. -..;.-- 14-3

(1) --lo.....en<.(wu.

-...:;r~

'-,'.11

~ Drj-----------------. .=cc-=============; 0-.-0- • --••-.-

\ 50% OF 0.2% YIELD STRENGTH ! 63-1

98- 01-2 11III11III

9S i I Ii!1 2 3 4 5 6



FIGURE 2.1-3

ALLOY 190 XHM

•Bright Clean

AEndurance Finish

65-1--..._._.- ..-----

... _.._.._---.~-----------102i--~.. -:··-·

i 20-4100+ -~ .•"--I -~- - ~ -----I -- .~---.---._- ---~-.-

1D8-:----

112 i 13-3 I'

I •

11 O~ .... -14::?J6.:~·~-----·- .-~~--- ..-~.~-- .. ; II -...-.-~.-,.-._-.- .. -~, .......-------, -""--"'-"~.-----.----, I, ., I

I10C ... -.~------.-.-..- ~OF 0.2% YIELD STRENGTH f J

1

18~A I104 .- "-'~'--'~-~~'~--""-""~---"--------en

::.c::I

(/)(/)

- Q)

.'Wl--

~en

~

..... «Cl' w

lJ..

32 ...J. ~__.~ .;".--.~- ..- --_ ....__.,., _."-'- ---------------.•--------- -~-----...-,---.

SOT-------(S~3--+- .. -·--t ._, I2.8 I ! i I

1 1.5 2 2.5 3.5 4 4.5



FIGURE 2.1-4

ALLOY 17410

.------ .. ·----5~1·-·,I

I I120 . •

'~.. i. 10

.2

% YILJJ) STHENGTJI 1-- '.-~-' ---~- Bright Clean II

;::,~=-t --~2~~-_j~2~ ~.. ' __..-~ I •

105~82"'------- -0-- -0 ----i--o Endurance Finish I

70--- --....- ·--··----··---27-2-·--·~-----~-··! •

o~ 4_...•_-~.._._.._--~._.~-.----)

..._-_._-....•....~~~-.

'-[75% OF 0.2% YI ELf) STRENGTH [- .--~-.---.----~~!

2/J-; .-- ..

~o-~

85~----~

9S'-~(f)

~I

(/)(/)- Q)

::," lo.......:r: (f)-:.

'- <l---J UJu..

~s--. -~.-.--.--..,--..-.----~----------.-~--.'"---~----.--.-.-.- ..-..-.-----.~------------- ..,

OF 0.2% YIELD STRENGTH [~----....

__._..... . _.-!-__. ~ __"---- ~-J, i

':/)--- -.---.--.-..-~~-l-·---~--f~~-~--·-~~----i ~~2H-ii' • '

4,5 : i I I I I

I.S 2 2.5 3 3.5 4


,4.5


FIGURE 2.1-5

;:,W~~

":'ole

Alloy 17200 1/4HT - Stress 89.7 KSITc:'>! Numbc:[ WAP75-1

1.1 ' , r' I , , ,

i I I H, 11,/":" I j II,,1 I I I ! , , ' ,,....J I i ".:/ \ I I I::: (! !! I ! 1:/ \ I I I

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:::(1 -/, 1: 1 ," I~ J. ,..-,- ,- V i Iz 1---- ' I-- () ------,-~V I : I I I I I I

I I )

1.0£+04 1.0£+05 1.0£+06CYCLES TO FAILURE

• ACTUAL 2 PARAM WEIBULL -- 3 f'ARAM WEIIlVLL - LOG 3 PARAM

COMPARISON OF STATISTICAL PREDICTIONS

FIGURE 2.2-1

Alloy 17200 1/4HT - Stress 93.2 KSITest Number WAP59-01

1.0E+08"1.0E+071.0£+05 1.0E+06CYCLES TO FAILURE

1.0£+04

iI

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cz

• AcrUAL -,- 21'ARAM WEIBULL -- 3 PARAM WEIBULL - LOG 3 PARAM

COMPARISON OF STATISTICAL PREDICTIONSFIGURE 2.2-2

'7

~~

!lO~.

....~

Alloy 17200 1/4HT - Stress 93.2 KSI) TEST NUMBER WAPOl-l

1.1

~ III;:;, I I

~ 0.88 ~LL t-'I <,,~,' 1/;tT~"~ I·r _..... ~I I 1.1

~ i 1 12.o ! ' ,\;;.. ill"'f-' I i >1f ~\- 0 66 ! L /;.fj..J • Ii I I....' I "- . I ,\~ I 1 I I'- r .," Z

..-:: I I I I I : ....~ , I I '1Il'\o I i I I' ! 1'1 '7J I S\

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I • ACTUAL --IIc- 2 PARAM WEIBULL0 3 PARAM WEIBULL z LOG 3 PARAM



5 0

w=z::;:,....J~ 0;...

;...f-'-~

~

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... ~- 0WN-.....-t.-£=z::0z

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L..

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1.0E+02 1.0E+03 1.0E+04 1.0E+05CYCLES TO FAILURE

1.0E+06 1.0E+07

• ACTUAL ,......". 2 PAHAM WEIBULL - 3 PARAM WEIBULL - LOG 3 PARAM

(:QM~AR1~iQ~_OLSTArISTICAL PREDICTIONS

FIGURE 2.2-4

Alloy 17200 1/4HT - Stress 95.9 KSI/TestNumberWAP4D-l '

_ ....... 2 J>ARAM WEIBULL - 3 PARAM WEIBULL - LOG 3 PARAM

..;",..:..,-.:~-:

1.0E+OS 1.0E+06CYCLES TO FAILURES

l-

il.OE+08

~

(..

I···--···_·-t--~······I--H+III·------------

1\

1.0E+07

1\

\ ...

1\

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\\\ "

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",

l/l\r-~

I

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,--..l<:::-·r·"

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--1--, ......

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1.1~ 1;:;;...J=1. 0.9:...b 0.8~'-"

~ 0.7-..J~

~ 0.6~ ~!10 o 0.5~

Cl::~

~ 0.4N

\oJt: 0.3..J

:$ 0.2~

~o 0.1z

0l.OE+03

• ACTUAL


FIGURE 2.2-5

l.OE+08 ..1.0E+071.0E+OS l.OE+06CYCLES TO FAlLURE

Alloy 17200 1/4HT - Stress 99.4 KSI-Test Number WAP23-1

"-~",::..,,,,,,,,,,,,,: ..".

1.0E+04

llrTmnnrTTTITmr-rrm~~~-rrnT~--,--r-~~r_1lmtttti-Mttttttr--t-fj1f~1;.y:;~.t-1\-+--H--W-U-U--LWlillJ7 " 1\

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----- V \.\o ~~-

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1.0E+03

~:;..:l...~~

~

0("t-'.....:l...~I:Q=-~'JQI:QI'll

0.£;.

=z::~

~

Q~N.....:l~...~0Z

• ACTUAl, _ 2 PARAM WEIUULL - 3 PARAM WElBULL - LOG 3 PARAM


:;;'"r":l

'. t

Alloy 17200 l/4HT - Stress 102.7 KSITlO\! ~umhl:r WAP23-2

, ' • I '! I[! -'----1 J 111.] '" Iii '\ \ I, i I ! I i I I I I I ,

! [il I j I , Iv' '1~ ]T- i ! ! Iii I I I Ii! J \ I I JJJ-' i; I I lUl--l

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Z 0.1 i • Iiii til I I UV , --,._-,j~I=:Lt _+1o 'Ii,

1.0£+03 1.0E+04 1.0E+05 1.0E+06 1.0£+07 1.0£+08CYCLES TO FAILURE

1.0E+09

• ACTUAL ...... 2 I'ARAM WEIHULL ---. 3 I'ARAM WErBULL - LOG 31'ARAM


Alloy 17200 1/4HT - Stress 107.4 KSITest Number WAPA2-1

1.0E+091.0E+05 1.0E+06 1.0E+07 ·1.0E+08CYCLES TO FAlLURE

1.0E+04

1.1

1

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

C1.0£+03

:.oJ:z::;:J..J

~;...;...0...~::::c~:c0~:z:::;;~'n

::J~

r_·'-~

~'.II --~-~

:z::0z

• ACTUAL .......... 2 P'ARAM WEI BULL .- 3 PARAM WEIBULL - LOG 3 PARAM


Alloy 17200 1/4HT - Stress 111.9 KSITEST WAP13-01

'-

1.1 ! I J , I I l) I' I I I I J ) I) I 'j j I I I j j r r J , ) I , j , j I J) j j j I j J I

/. - i1i 11 I I II! III' I I I1I1I1I I I I"!.ill I I I 1I1111 I I I Ill/Ii;:;,,.J (( ''''::: d..7 i :III

" , ;

~ i.: r~

~ 0.8 I I •

-' I~,~ !t: 0.7, '! 1\1 1 '

~ O.~ / 't II1I1111 I Io 0.;, , 7 \=' f \\::., {\ t

~ 0.4 I ;,11 ,~ \~ 0.3 1/ I \\ ''; 0.2, : \\,::; ! ./ \5 () 1 I / / i\ 1 I I I J 111

Z ., I . / / 1/ .... 111111111o J ...._. - ...... ../- \0 1III1.0E+03 l.OE+04 l.OE+05 . l.OE+06 l.OE+07 l.OE+08

CYCLES TO FAILURE

;tr.;~

~

• ACTUAL .......... 21'ARAM wmBULL - 3 PARAM WEIBULL - LOG 3 PARAM


Alloy 17200 1/4HT - Stress 112.4 KSITEST number WAP20-1

1.0E+08,.1.0E+07I

1.1 I11I II _ - - -1

1 I I I / I II111 I I / I I11II I {1"/[>1O.~ , I~ 1/ '.... I' I

f,' \;', \10.8 I/,; 'f

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• I I I I IIIII1 I I 11111/1 > I

0.5 I / I I I I I I I I IIlf, "I'

004 I / : { ;' \~O.~ I /" I ~.•

02' / / / .

. I 'I // . / • I \0.1 . /' /' \1:\

I ~--- - / ~() ....-'-- .._- \~

1.0E+03 1.0E+04 1.0E+05 1.0E+06CYCLES TO FAJLURE

W0::~-=2~

~

0>-;...:-...;-::Q~~::Q

:;

0r-0::

~

c..""' 0--.l

WSI--~-~0::0z

• ACTUAL .......... 21'ARAM WElHULL - 3 I'ARAM WEIBULL - LOG 3 PARAM

COMPARISON OF STATISTICAL PREDICTIONSFIGURE 2.2-10~._------_..__._------_.


------,,-- 21'ARAM WEIBULL - J I'ARAM WEIBULL - LOG 3 PARAM

~",.,:::,~*" .. :,''''

l~ I 1\

£)1 I 1\\

l.OE+06

\,"t{\,

\\1t

\'1\

~\

£t:1

-

/1 1/// /

jII!

#1 I r~

f!I\([ff/ I \~// \1,

/7

1//,1.0E+04 l.OE+05

CYCLES TO FAILURE

.~-_ ..,.,

1.1

~ 1;:J,.J=1. 0.9:...~ 0.8'..I

>-t-< 0.7-,.J~ 0.6

"'tl • ~~::. o 0.5110

~ ~

~~

Cl 0.4w~ 0.3,.J...r:;; 0.2

"~ 0.1

01.0E+03

• ACTUAL


Alloy 17200 1/4HT - Stress 122.6 KSITest Mumber WAPAl-l

1.0E+05 l.OE+06CYCLES TO FAILURE

\

"\"

1\

1.0E+08l.OE+07

!~I".......1"....

-•• J-'""'''-.~:t...

• ........1

--7

".1.11..........

1.1~

~ 1;:; 1"d 09 ri

,\- --1. •..... .......~ 0.8 i,..,;

1"\. I \;;...r-- 0.7 ! \ II-..J:.; 0.6- --1.

V.Y- ~!1Ct o 0.5r)

='"'"' ::: 0.4 / h"0

'-'0, j....~

~ O.3r

-I 11~

:;; 0.2I='o 0.1 ...---,/ Iz ..-

0 -1.0E+03 1.0E+04

• ACTUAL ..-...... 2]'ARAM WElnULL - 3 PARAM WEIBULL - LOG 3 PARAM


FIGURE 2.2-12

'iData .Paints for Endurance TestingRepresent the 50% Failure Pre·d·iction

r Using the 3 Parameter Weibull Distributionof the Log of Cycles to· Failure

.....

.•.•.J

,, .r-

r I [J I" J .JIA>< i~

c: ,pI

,r-1

~ .~

L

l

"':i~

:r.;'.11o

170165

_ 160'(l 155~ 150CJ'J 145~ 140~ 135E-CJ'J 130_ 125~ 120= 115~

~ 110...; 105~ 100-< 95~. 90~ 85

80751E+04 lE+05

ALLOY 17200 1/4HT

lE+06 lE+07 IE+08CYCLES TO FAlLURE

IE+09 IE+IO

T~ BRIGHT CLEAN ..... ENDURANCE FINISH "'" ASTM R=O

COMPARISON OF TEST RESULTSFIGURE 2.3-1

I IData ~<?LI1s( for En9urance Testing

,,I

'"Represent the 50% Failure PredictionUsing the 3 Parameter Weibull

! '" Distribution of the Log of Cycles toIi Failure

~V

II i/ II I

"-" "'"I I

c- /I I

I

I....

I ! ..I i I

"-, I

I

17;)1701f;;)

- 1(;0'f, ISS~

I Sf),'l: 11 ;)':fj

1,10~

=t: 1~~:);;...J ~~ [)z'- 12;)c.

:;; 120- 1J:.,"";

c.:;;. - 11 ()~

~"~

]rJ:"'.J1 --

~

100<r .... "' %-;;;;.

~JfJfJ~(J .J

(\0'r)

11-:-,,01 J E+O;)

ALLOY 17200 HT

1E+0(; IE+07CYCLES TO FAILURE

1E+OB 1E+09

BRIGHT CLEAN .. ENDURANCE FINISH ;+' ASTM R=()


Data Points for Endurance Te~ting --Represent the 50% Failure PredictionUsing the 3 Parameter Weibull Distributionof the Log of Cycles to Failure -

~ - '"- ..,-"

~

I

"'"'--.

"

I

-'Jj

~I

'JJ'Jj

~~

CrJ-~;:J-~

~~

~

(J'Q~

~'JI~.."

~

~~~

175170165160155150145140135130125120115110105100

95908580751E+04 1E+05

ALLOY 190XHM

1E+06 1E+07CYCLES TO FAILURE

1E+08 1E+09

[] MILL FINISH .. ENDURANCE FINISH "'" ASTM R=O

COMPARISON OF TEST RESULTS

FIGURE 2.3-3

1E+081E+071E+06CYCLES TO FAILURE

1E+05

! i I i j I,

I I Data Points fercEndurance Testing, ,I

\

I

Represent the 50% Failure PredictionI I\ I " , Using the 3 Parameter Weibull DistributionI • );.LV

I I"

of the log of Cycles to Failure

;r II L I

I

I_i? i- -i?I I I I

,I I I /' j

i I iI ,

,~ ,

I i II ,

! II I I

! I ~

, I I

-~"'.

~

~'-'l:,-~~-~-~"'.

120" ALLOY 17410 I115

::;: 110~ 105'Jj 100'Jj

9590858075706560

, ~ ~-I ;-. ::J::J

50451£+04

'JI.~

"'=~on':>

MILL fINISH .. ENDURANCE FINISH ;¥ ASTM R=O


ALtOY 172(] 0 1/4 HT:3 PAPA\1. WEfFJULL OP IDG CYCLES TO PAIL

150 155 160 165 170

""

4,Ol,----r--,--~-r__,-_____r-__r---,-___r-_,_-_r_-_,_-__r_-_,__-,_-r_-r__-

3,8 7' <, "

. 3,6+---\--t------t--t---t--+--+--+---+--+--+---+---+--i----i--+--1~ 3.4 ;,c

~ 3.2 ,~;:: 3.0~~ 2.8 " :: 2.6 "~ I....- 2.4 ~

:-; 2.2 1----" • ..... !,..- 20 -...... " ~ ~ ,--;. 7. ~ ....... ~ ,

::: 1,8 -..... ~"./ 1,6 ,........ . , I1 4 X ------ ........ ~'.

....- 1,21

~" ,

~ 1,0; ", ~. "'--I---. .... "'!'-. ,~

~ 0.8, x X r----.. ........;:. 0.6 i x' k... '/.- ' ,I~.... 'i 7r

0.4 i /- r------..... ~' Ivg:~i I ~"'"

85 90 95 100 105 110 115 120 125 130 135 140 145STEES'S - KSl

'J!"-

~

=~":>

X Hl~rr;)1T r;Lr:r.rl

-- nr; Llrlr~ F'll

jV f)f([)PPf:D por~lE A. ElWUR/dICE FINlSH

........... EF I.lf'" Fit Z DHOPPED PDJPTS ITREND OF WEIBULL ALPHA PARAMETER

FIGURE 2.4-1

ALLOY 17200 1/4HT3 PARA..\f;, WEIBULL OF LOG CYClES TO FAIL

)~

~-+-FFI I:>_l-- -I-

/1

.- I

I I

~

o •

I I

J ~_ e----+-- f--'-- ~ I I,'- . -t---+-+--=~ 1 I_ _,- I - ~--='if--_~ IT······ x -. I 1.....- - -

'" f--:=t+ fe-.-'+--~ I >~ --c=.r~ J.----J---.. I --r ~ 0 ~a '-- ~ '~"'1 t ---I _~ f--'1- 1 *'. r- f--f-- -

'-- _~.,.'_ ~ I - X f--_f--

..' ~. I 1k-""A ... -+-f-- y r 0 I II -I ~ J 1---1 ' ' ---1--1 x "0 I I I

[.f-- 1-'-'-. f-- I 1 -

~ I r-- 1=+=~ I _ -- f----i -,.{--~ ->--I' 1'-!r-~f--f-- 1 ~---;;rf-- l---+--f-- . I, -r-r-~f--+-----+- I -=

J I II f--

J 1----'-1

7.67.4

. 7.2S 7.0-S 6.8~ 6.62 6.4~ 6.2::: 6.0("' 5.8~ 5.6~ 5.4

5.2I 5.0

:::: 4.8;:) 4.6,[j..... 4.4:.,

>- 4.2.- 4.0

3.83.6

85 90 95 100 105 11 0 115 120 125 130 135 140 145 150 155 160 165 170STEES'S - KSl

'"0~

TQ-:;

'Jl'Jl

X @JGIlT eLSAH

-- m; Lin', fil

* DROPPED POllJTS A ENDURANCE FINISH

.......--.. Ef LIflI' fit Z DROPPED POINTS

'-

~

TREND OF WEIBULL BETA PARAMETER

FIGURE 2.4-2

ALlDY 17200 1/4HT3 PARillJ. WEffiULL OF LDG CYCLES TO FAIL

5.0 I I I I I I I i I I I I I i I I i

4.8 I I .

~. 46m1J=..... 1 I,'".:, 4.4 A· 1 I I L;c..

G~ 4.2 '....

~ :~E8 I IEEEEl I n=EE-Ec 3.6~ 3.4 I I I I I I I II I I ! I I I I I I

I

J~~~ I §iE§2.41 I I I I I x I ! I I I ! i I I I I I

2.21 I I I I I I I j I I i I I I I I I85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170

STRESS - KSl

~:w'1Q~

~Q\

X rmlGHT CLEfl.lJ

-- Be !.iw: Flt

*' Be DROPPED POJ!JTS ..... ENDURANCE FINISH

........... EF' Line Fit L EF DROPPED POINTS

/

TREND OF WEIBULL XO PARAMETER

FIGURE 2.4-3

-==~til-..J

ALlDY 17200 1/4HT - BRIGHT CLEAN3 PARAM WEIBDlL OF LOG CYCLES TO FAIL

150iii I I I I i j I I) iii iii iii i I I I i I I i

145 "'"\"'j,140 ,,_ .135 . ".~.. ,.

\ ~ '.130 . .:.. .

~ 125 \ .;.. .

~ 120 \."" '. ......

~115 - 11111

2 110 '\.~ '. '.r;. 105 \ - -'.....

j ~'~••

100 ., - ", ".95 \ .

\ a ..

90 \ _ .

85 \ -'"\' l80

... '. '._ "'1'

1E+04 1E+05 1E+06 1E+07

Cycles to Failure-- J % F'ailurE:s "'" 10% F'ailUfE:S .. 50% Failures ...._..... 90% fAILURES

STATISTICAL FAILURE PREDICTION

FIGURE 2.4-4

CONCLUSIONS

3.1 ENDURANCE TEST METHOD

The "Endurance Test" method is an ideal method of determining the fatigue

life of strip spring alloys. The "Endurance Test" specimen is a manufactured

spring, and must pass through all the necessary manufacturing operations that a

typical strip metal spring would require. This subjects the "Endurance Test"

specimen to all the same side effects and variability of these processes. The

"Endurance Test" specimen is a realistic simulation of an electrical contact spring.

A special fatigue tester was designed to test the "Endurance Test" specimen

called the "Endurance Test" machine. A major feature of the "Endurance Test"

machine is the ability to test up to 48 specimens at a time. This was a significant

advantage because enough test data to analyze the fatigue life statistically was made

practical only because of the specimen capacity of the "Endurance Test" machine.

3.2 ROGUE TEST RESULTS

The test results show that the fatigue life of a few test groups deviate

significantly from the majority of the test groups measured in this program. oThe

cause of these deviations could not be determined, and the rogue test groups could

be identified only by the trend of the majority of the test data. Fortunately the

rogue groups stood out from the majority of the test data and could be separated.

Rogues (batches ofmanufactured springs which lack consistent properties) have been

Page 58

common in precision metal stamping of Copper Beryllium alloys. The cause of

rogues still remains a mystery. The rogues must be due to some variable in the

manufacturing process which has a serious detrimental effect on the fatigue life of

the formed spring. In comparing the "Endurance Finished" data to the general

production "Endurance Test" specimens, it was noticed that in general the

"Endurance Finishing" process produced higher fatigue life and better consistency

than the standard manufacturing process alone. This reduced the frequency of

rogues, but they also happened in "Endurance Finish" tests.

3.3 FINITE ELEMENT ANALYSIS

Finite Element Analysis (FEA) proved to be accurate in predicting the stress

levefin formed parts. This can be seen in comparing the fatigue test data produced

using the ASTM fatigue test method data to the "Endurance Test" data which used

FEA to analyze the "Endurance Test" specimen stress. The Stress on the ASTM

specimens was measured using strain gauges and the elastic modulus from tensile

test data. The stress distribution on the ASTM fatigue specimens is very uniform,

and can be predicted accurately using a strain gauge. The complicated stress

distribution present on the endurance test specimen is to complicated to measure

using strain gauges. Also standard beam equations are not suitable for highly

deflected structures due to edge curl of the structure.

F'imte element analysis, specifically-geometrically ··non-Iinear analysis can

Page 59

accurately predict the value and distribution of stresses in thin metal springs.

3.4 FATIGUE TEST RESULTS ON ALLOY 17200

The fatigue test results on alloys 17200 1I4HT and HT were similar in shape,

with the stronger HT material producing about the same fatigue life with a 20 KSI.increase in stress. This is_~hown in Figures 2.3-1 and 2.3-2. These alloys are

chemically identical, and are differentiated only by the amount of cold reduction

after the final solution annealing. The difference in the .2% yield strength for these

alloys is 36 KSI, and the difference in the fatigue results represented about half of

the difference in the .2% yield strengths.

The fatigue life of the mill hard version of alloy 17200, the XHM temper,

produced significantly lower fatigue life than the HT materials. The fatigue test

results are shown in Figure 2.3-3. The .2%) yield strength of alloy 17200 XHM is

lower than that of the 1I4HT and HT versions of this alloy which partially explains

the difference in fatigue life. This can also be explained by the presence of residual

forming stresses in the mill hard material. The 1I4HT and HT materials are solution

aged after forming which removes most of the forming stresses. Specific material

properties for the materials tested are given in Table 1.0-1

3.5 FATIGUE LIFE OF ALLOY 17410

Alloy 17410 is also a Copper Beryllium alloy, but has a different chemistry

Page 60

and metallurgy. This is a special alloy with lower strength than conventional Copper

Beryllium alloys, but with higher conductivity. It is also a mill hard alloy, and

includes residual forming stresses in the finished "Endurance Test specimen. This

data is shown in Figure 2.3-4. The specific material properties for this alloy are

given in Table 1.0-1

3.6 STATISTICAL DISTRIBUTIONS

The most important outcome of this thesis is the determination of proper

statistical methods to characterize metal fatigue test results. The commonly

recommended two and three parameter Weibull distributions did not accurately

portray the fatigue test data. When the logarithms of the cycles to failure is used,

the three parameter Weibull distribution produces a reasonable match to the data

that is being characterized. After the statistical analysis, the probabilities of failure

are determined. The antilog of the cycles to failure predicted by the probability

distribution give the true cycles to failure information.

Like all statistical techniques, the match is an empirical match, and is not

directly based on a physical model. One reason that the three parameter Weibull

function was chosen is because it predicts that there is a threshold value before

which there is an infinitely small probability of failure. The fatigue data produced

in this program strongly indicated that this is true. Another reason for choosing the

Weibull distribution is that the pattern of failures that were observed produced a

Page 61

r

non-symmetrical probability distribution. The Weibull distribution accounts for the

non-symmetrical data. The mathematics used to calculate the three parameter

Weibull distributions three parameters are complicated, but the iterative technique

used in this thesis is straight forward and well suited to computer analysis.

Page 62

REFERENCES

1. Endurance Finishing, Endurance Testing, & Bright OeanInstrument Specialties Co., Inc.Delaware Water Gap, PA - 1938

2. AS1J\i-B593-85AS1J\i (American Society for Testing Materials)Philadelphia, Pa - 1985

3. AS1J\i fatigue test data and test material courtesy ofSharon Shriver and John RatkaBrush Wellman Inc. - Oeveland, Ohio - 1987

4. NISA IT - Structural Finite Element Analysis ProgramEngineering Mechanics Research CorporationTroy, Michigan - 1987

5. Materials Handbook 9th EditionVolume 8 - Mechanical TestingASMI Press 1986Metals Park, OhioPages 632 to 635, 714 to 717

6. Engineering Statistics - Macmillan Publishing Company 1987by Robert V. Hogg and Johannes LedolterPages 116 to 123

7. Quattro Pro 3Borland International. Inc.Scotts Valley, CA - 1991

Page 63

.....

.APPENDIX - A

Page 64

ALLOY 17200 1/4HT

Page 65

F I L E = WAP3-1.WQl

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 1I4HT

NOTES = ENDURANCE FINISHED

% FAILURES ESTIMATED FEAACCEPTABLE CYCLES TO STRESS

OBTAIN KSI% FAILURES

1 24,680 91.725 269,536

10 774722 STDDEV50 12278897 2.48595422

IALPHA = 21019757.752895,IBETA = 0.68178212633819

AVERAGE AVERAGE83:03 91.72

81.4 90.0 1 10000000089.3 98.5 1 350580082.2 90.8 1 10000000082.1 90.8 1 7,486,50083.9 92.7 1 4,280,90083.8 92.6 1 100,00000082.1 90.7 1 729140079.6 88.0 1 6,13670082.6 91.3 1 4,374,00081.7 90.2 I 3858,40085.0 93.8 1 3,070,40082.7 91.3 1 4,302,200

SPECIMEN THICKNESS# INCHES

1 0.00992 0.00993 0.009854 0.00995 0.009856 0.009857 0.009958 0.00989 0.00985

10 0.009911 0.0112 0.00985

LOAD STRESS FEALBS K S I STRESS

0.50030.54880.49990.50480.51060.50980.50950.47920.50250.50180.533

0.5028

Page 66

cyclesto fail

FILE= WAP59-1

OFFSET = 0.9995

WIDTH = 0.,376

MATL. = ALLOY 17200 1/4HT

NOTES =



1 58,170 93.225 235,187

10 435.865 STDDEV50 2.190.653 3.30043375

IALPHA = 2999159.8~1BETA = 1.16674636

3.5064E-Q7

AVERAGE AVERAGE0.0022 84.35 93.22

cyclesf1'1

STRESS FEAS I STRESS

SPECIMEN THICKNESS LOAD# INCHES ,grams K to at

1 0.0096 235.40 89.8 99.2 1 3,5607002 0.0096 223.46 85.3 94.2 1 26899003 0.0096 216.53 82.6 91.3 1 6,132,5004 0.0096 213.51 81.5 90.1 1 832,4005 0.0096 221.34 84.4 93.3 1 545,800

6 0.0096 235.36 89.8 99.2 1 600,6007 0.0096 219.35 83.7 92.5 1 872.2008 0.0096 217.67 83.0 91.8 1 1963,600

9 0.0096 214.91 82.0 90.7 1 2330.70010 0.0096 216.48 82.6 91.3 1 9609.20011 0.0096 209.89 80.1 88.5 1 3846.20012 0.0096 228.93 87.3 96.5 1 946,500

Page 67

.FILE= WAPl-l

OFFSET = 0.9995

WIDTH = 0.376



OBTAIN KSI% FAILURES mean

1 52,874 93.245 155,015

10 249,271 STDDEV50 864,113 4.26281017

IALPHA = 1100551.5~1BETA = 1.51537126

AVERAGE AVERAGE84.42 93.24

77.6 85.8 1 288260082.6 91.3 1 77060082.6 91.3 1 44870083.1 91.8 1 102610083.7 92.5 1 53760091.9 101.4 1 79590081.6 90.2 1 79730090.1 99.3 1 221120089.3 98.5 1 44420081.8 90.5 1 57580085.7 94.7 1 43790082.9 91.6 1 821700

,,"


1 0.00982 0.00973 0.00974 0.00985 0.00976 0.00977 0.00988 0.00989 0.0099

10 0.009711 0.009912 0.0099

LOAD STRESSLBS KS I

0.46740.48720.48720.50040.49380.54230.49160.54230.549

0.48280.52690.5093

; Page 68

FEASTRESS

cyclesto fail

FILE= WAP74-1

DATE = 3/22/88

OFFSET = 0.9995

WIDTH = 0.376


NOTES = BURR OUTSIDE



1 1,422 94.865 8,304

10 18,106 STDDEV50 139,232 3.17908289

\ALPHA = 207061.251;1BETA = 0.92349846

6.3428E-1O


cyclesf: '1

STRESS FEAK S I STRESS

SPECIMEN THICKNESS LOAD# INCHES grams to at

1 0.0097 240.05 89.7 99.0 1 791002 0.0097 232.37· 86.8 95.9 1 818003 0.0096 232.93 88.9 98.2 1 14180004 0.0097 239.90 89.7 99.0 1 1144005 0.0097 227.03 84.8 93.8 1 112,3006 0.0097 225.30 84.2 93.0 1 1204007 0.0097 226.05 84.5 93.4 1 853008 0.0097 223.60 83.6 92.4 1 1119009 0.0097 231.28 86.4 95.5 1 96600

10 0.0098 222.12 81.3 89.9 1 92 10011 0.0096 233.58 89.1 98.4 1 16060012 0.0097 217.67 81.3 89.9 1 148,400

Page 69

F IL E = WAP40-1

a DATE = 11/17/87

OFFSET = 0.9995

WIDTH = 0.376


NOTES = (DREW'S CONTROL) BURR OUT - # 10 DENTED



1 33,556 95.875 154,981

10 304607 STDDEV50 1 785 470 6.03182452

!ALPHA= 2518680.52 1

BETA = 1.065278152.408E-09


cyclesf1"l


SPECIMEN TIllCKNESS LOAD# INCHES ~ to aI

1 0.0093 230.64 93.8 103.6 1 2339002 0.0093 221.02 89.9 99.3 1 45062003 0.0092 222.50 92.4 102.2 1 3,197,3004 0.0092 228.64 95.0 104.9 1 1349,7005 0.0093 222.44, 90.4 100.0 1 1,708,4006 0.0093 216.15 87.9 97.2 1 5986007 0.0094 202.91 80.7 89.3 1 351 5008 0.0094 212.82 84.7 93.6 1 257,0009 0.0093 201.28 81.8 90.5 1 5870800

10 0.0093 212.04 86.2 95.3 1 128470011 0.0094 197.31 78.5 86.8 1 4,95610012 0.0093 195.53 79.5 87.9 1 5,193,800

Page 70

FILE= WAP23-1

~

OFFSET = 0.9995

WIDTH = 0.376


NOTES = BURR ON OUTSIDE OF BEND



1 61,438 99.425 562582

10 1,495,950 STDDEV.I50 19340,976 1.83580644

IALPHA = 31822768'~1BETA = 0.73603467

2.4277E-I0


90.0 99.3 1 13,633,60087.6 96.7 1 1212470092.3 101.8 1 13,775,10091.3 100.7 1 1,532,00087.5 96.6 1 6,536,90090.8 100.2 1 10000000090.5 99.8 1 1 135,20088.9 98.1 1 6,005,40089.7 99.0 1 745000092.8 102.4 .~ 'i 10000000088.4 97.6 )1 10000000091.7 101.1 1 100,000,000


1 0.00982 0.00983 0.00964 0.00985 0.00986 0.00977 0.00988 0.00989 0.0097

10 0.009711 0.009812 0.0097

LOAD STRESSLBS K S I

0.54190.52760.53310.54970.52680.53550.54490.53530.52890.54770.53230.5407

Page 71

FEASTRESS

cyclesto fail

FILE = WAP23-2

OFFSET = 0.9995

WIDTH = 0.376


NOTES = BURR ON INSIDE OF BEND



1 23,543 102.725 291,116

10 883916 STDDEV50 16171533 1.51541827

I:ALPHA= 28467249'~1BETA = 0.64811979

1.9282E..Q8


94.2 103.7 1 6,509,70093.7 103.2 1 1533,00094.0 103.5 1 100000,00091.2 100.7 1 1436,90093.9 103.5 1 100,000,00091.8 101.2 1 18411.10094.7 104.1 1 3412 10093.6 103.1 1 100,000,00090.6 100.0 1 19372 70092.6 102.1 1 506,60096.0 105.6 1 7765,20092.5 101.9 1 100,000,000


13 0.009814 0.009815 0.009816 0.009717 0.009718 0.009819 0.009920 0.009821 0.009722 0.009823 0.009924 0.0098


0.56710.56410.56610.53830.55390.55300.58160.56380.53480.55760.59010.5569

Page 72

FEASTRESS

cyclesto fail

FILE= WAP23-4

OFFSET = 0.9995

VVUD1lI = 0.376


NOTES = ENDURANCE FINSHED - BURR ON OUTSIDE OF BEND



1 32,238 102.755 268.662

10 685,286 STDDEV50 7,946,045 1.60598217

IALPHA = '12800050.;IBETA = 0.76873379

9.l336E-1O


94.8 104.2 1 8,930800

93.3 102.8 1 100,00000091.7 101.1 1 18,873,20091.4 100.7 1 72250092.9 102.3 1 6,500,70091.9 101.2 1 8,076,90092.6 101.9 1 7.31680092.5 101.9 1 21,63520096.2 105.7 1 2,65160095.6 105.1 1 7.992 80094.9 104.2 1 2,35960092.4 101.8 1 1,756,700

SPECIMEN 1lIICKNESS# INCHES

37 0.009938 0.009939 0.009940 0.009941 0.009942 0.009843 0.010044 0.009945 0.009946 0.009947 0.010048 0.0099


0.58230.57360.56380.56160.57080.55310.58090.56860.59110.58740.59470.5679

Page 73

FEASTRESS

cyclesto fail

FILE= WAP23-3

OFFSET = 0.9995

WIDTH = 0,376


NOTES = ENDURANCE FINSHED - BURR ON INSIDE OF BEND



1 1l,074 105.955 116789

10 330,537 STDDEV50 5031152 1.44522256

IALPHA = 8545119'~1BETA = 0.69191072

6.9506E-10

AVERAG AVERAGE0.0013 96.39 105.95

94.5 103.9 1 100,00000096.8 106.3 1 1,821,70095.4 104.9 1 6,28940097.8 107.5 1 595,30097.4 107.0 1 6,584,20098.2 107.9 1 835030096.8 , 106.4 1 264260093.7 103.1 1 606150096.9 106.4 1 472740098.0 107.6 1 384900095.6 105.2 1 469680095.6 105.2 1 1,169,000


25 0.009926 0.010027 0.009928 0.009929 0.0099 ""30 0.009931 0.009932 0.009933 0.009934 0.009935 0.009836 0.0099


0.58050.60710.58620.60120.59870.60360.59500.57550.59520.60210.57540.5877

FEASTRESS

cyclesto fail

Page 74

FILE= WAPA2-I

DATE = 10/19/88

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 1/4HT?

NOTES = 800 CPM - TERMINATED@ 51,081,500

% FAILURES ESTIMATEDACCEPTABLE CYCLES TO STRESS


1 289 107.45 10,901

IO 54,139 STDDEV50 3590,214 5.79714014

!ALPHA= 811937~1BETA = 0.44913514

3.9769E-10


cyclestofl'l

STRESS FEAKS I STRESS

SPECIMEN THICKNESS LOAD# INCHES grams al

1 0.00945 0.5344 95.4 105.3 1 100,000,0002 0.00970 0.5657 95.9 I05.6 1 49,8753003 0.00970 0.5752 97.5 I07.3 1 2473004 0.00960 0.5573 96.4 106.3 1 5323005 0.00980 0.5428 90.1 99.4 1 3IO 0006 0.00985 0.5741 94.4 103.9 1 1977007 0.00925 0.6173 115.1 126.2 1 7669008 0.00960 0.5734 99.2 109.2 1 161,6009 0.00985 0.6263 103.0 112.8 1 247300

10 0.00955 0.5199 90.9 I00.4 1 36120011 0.00960 0.5997 103.8 114.0 1 27800012 0.00965 0.5271 90.3 99.7 1 17860013 0.00965 0.5670 97.1 106.9 1 1836590014 0.00970 0.6065 102.8 112.9 1 872540015 0.00975 0.6096 102.3 112.3 1 754520016 0.00970 0.5721 97.0 106.8 1 2,261,70017 0.00975 0.6023 lOLl 111.0 1 10000000018 0.00975 0.6012 100.9 110.8 1 97800019 0.00935 0.4905 89.5 98.9 1 10000000020 0.00960 0.5542 95.9 105.7 1 155200021 0.00955 0.5516 96.5 106.3 1 10000000022 0.00930 0.5287 97.5 107.6 1 111620023 0.00935 0.5084 92.8 102.5 1 6,532,80024 0.00975 0.5721 96.0 105.7 1 6484,400

. Page 15


OFFSET = 0.9995

WIDTH = 0,376

....MATL. = ALLOY 17200 1/4HT

NOTES =



1 154,603 111.895 288.833

10 380641 STDDEV50 783.836 1.28977672

IALPHA = 902108.80~1BETA = 2.60797815

-4,363E-Q9


103.9 113.7 1 909"500

101.6 111.4 1 1405,900100.7 110.5 1 533 100100.2 109.9 1 1.326.500101.5 111.3 1 513,200102.7 112.5 1 1064600104.1 114.1 1 421.900100.7 110.5 1 902,600103.2 113.0 1 379.100102.9 112.8 1 546.600101.2 111.0 1 954.500102.4 112.2 1 614,800


1 0.00992 0.00993 0.00994 0.00995 0.00996 0.00997 0.00988 0.00999 0.0099

10 0.009911 0.009912 0.0099


0.63830.62450.61890.61580.62380.63100.62670.61890.63420.63260.62190.6292

Page 76

FEASTRESS

cyclesto fail


OFFSET = 0.9995

WIDTH = 0.376


NOTES =



1 43,743 112.395 102,433

10 149,154 STDDEV50 398,778 1.26078502

IALPHA = 482864.56;IBETA = 1.91560459

2.4636E-08


102.3 112.2 1 306,800102.6 112.6 1 1,070,100101.0 111.0 1 456,900101.7 . 111.6 1 326,000102.9 112.9 1 375,100102.1 112.0 1 156,700

102.8 112.9 1 276,700

102.3 112.2 1 306,800103.2 113.3 1 572,100104.9 115.1 1 237,700

101.0 110.8 1 780,700100.6 110.4 1 360600104.0 114.1 1 298800


1 0.00982 0.00973 0.00974 0.00985 0.00986 0.00987 0.00978 0.00989 0.0097

10 0.009711 0.009812 0.009813 0.0097

LOAD STRESSLBS KSI

0.61580.60510.59580.61220.61990.6146

0.60650.61610.60880.61890.60790.60550.6135

FEASTRESS

cyclesto fail

Page 77

FILE= WAP73-1

DATE = 3/10/88

OFFSET = 0.9995

WIDTH = 0.376





1 11,683 112.755 18906

10 23,384 SIDDEV50 40,790 3.63532579

IALPHA = 45452.9804 1

BETA = 3.38602084-7.434E-08


cyclesi1'1


SPECIMEN THICKNESS LOAD# INCHES In'ams to at

1 0.0097 280.23 104.7 114.9 1 34.5002 0.0094 244.29 97.2 107.2 1 451003 0.0095 259.45 lOLl 111.3 1 44.1004 0.0094 252.96 100.7 110.9 1 658005 0.0095 262.88 102.4 112.7 1 26,3006 0.0096 269.52 102.8 113.0 1 46.9007 0.0094 244.78 97.4 107.5 1 49,2008 0.0097 268.50 100.3 110.3 1 23,5009 0.0096 267.22 102.0 112.1 1 31,100

10 0.0096 280.83 107.1 117.5 1 6120011 0.0096 275.93 105.3 115.6 .<t 31,80012 0.0096 287.28 109.6 120.0 1 29,600

Page 78

F I L E = WAP18-l.WQ1

OFFSET = 0.9995

WIDTII = 0.376





1 67,298 113.785 220249

10 371.80250 1463641

IALPHA = 1910814.43:1BETA = 1.37475522

8.6467E-Q8


SPECIMEN TIIICKNESS LOAD# INCHES LBS

STRESSKSI

FEASTRESS

cyclesto fail

1 0.0097 0.6158 104.4 114.5 1 1742002 0.0097 0.6022 102.1 112.1 1 45061003 0.0097 0.6223 105.5 115.7 1 1,3273004 0.0097 0.6186 104.9 115.0 1 1,989,3005 0.0097 0.6059 102.7 112.8 1 1,912,2006 0.0097 0.6167 104.5 114.7 1 1433,0007 0.0097 0.6073 102.9 113.0 1 2940008 0.0097 0.6162 104.5 114.6 1 2,3879009 0.0097 0.6131 103.9 114.0 1 610 100

10 0.0097 0.5901 100.0 110.0 1 332120011 0.0097 0.6142 104.1 114.2 1 2,39370012 0.0097 0.6174 104.7 114.8 1 654000

Page 79

FILE= WAPI4-1.WQl

OFFSET = - 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 1I4lIT

NOTES = ENDURANCE FINIS¥



1 92,228 115.285 176,753

10 235,573 STDDEV50 499,615 2.19038026

\ALPHA = 578308.23~IBETA = 2.50574006

5.0269E-08


SPECIMEN THICKNESS LOAD# INCHES LBS -


cyclesto fail

1 0.0098 0.6255 103.9 113.9 1 8556002 0.0098 0.6342 105.3 115.3 1 371 6003 0.0098 0.6482 107.6 117.7 1 250,7004 0.0098 0.6378 105.9 116.0 1 2667005 0.0099 0.6542 106.5 116.4 1 464,4006 0.0098 0.6115 101.6 111.4 1 337,6007 0.0098 0.6083 101.0 110.9 1 5823008 0.0097 0.6322 107.2 117.4 1 957,1009 0.0098 0.6467 107.4 117.5 1 284700

10 0.0097 0.6236 105.7 115.9 1 582,30011 0.0099 0.6402 104.2 114.0 1 51450012 0.0098 0.6435 106.9 116.9 1 664,000

Page 80

F I L E = WAP58-1

OFFSET = 0.9995

WIDTH = 0.376


NOTES =



1 111,697 116.455 151331

10 173049 SIDDEV50 245809 1.86212829

IALPHA = 263180.303,1BETA = 5.36743839 i

-9.862E-08


cyclesf1 '1


SPECIMEN THICKNESS LOAD# INCHES ~ams to at

1 0.0096 276.23 105.4 115.7 1 2477002 0.0096 283.66 108.2 118.6 1 2188003 0.0096 275.76 105.2 115.5 1 2760004 0.0096 278.38 106.2 116.5 1 2856005 0.0096 277.55 105.9 116.2 1 198,2006 0.0096 282.14 107.6 118.0 1 186,1007 0.0096 281.44 107.4 117.7 1 2143008 0.0096 270.05 103.0 113.2 1 246,0009 0.0096 284.43 108.5 118.9 1 334400

10 0.0096 283.40 108.1 118.5 1 31490011 0.0096 273.55 104.4 114.6 1 20080012 0.0096 271.50 103.6 113.8 1 193,700

Page 81

FILE = WAP72-1

DATE = 3/9/88

OFFSET = 0.9995

WIDTH = 0.376



% FAILURES ESTIMATED FEAACCEPTABLE CYCLES TO ~SS


1 13,158 121.015 21,134

10 26,054 STDDEV50 45,055 5.4380233

IALPHA = 50121.251~1BETA = 3.43952036

-2.431E-07


cycles£; '1


SPECIMEN THICKNESS LOAD# INCHES ,grams to at

1 0.0094 301.72 120.1 131.1 1 34,5002 0.0095 293.30 114.3 125.0 1 47,6003 0.0097 290.76 108.7 118.9 1 38,0004 0.0097 290.26 108.5 118.7 1 417005 0.0096 286.02 109.1 119.6 1 30,6006 0.0095 295.96 115.3 126.1 1 26,3007 0.0097 266.12 99.5 109.4 1 59,1008 0.0097 294.36 110.0 120.3 1 44,5009 0.0097 293.70 109.8 120.1 1 76100

10 0.0097 297.51 111.2 121.5 1 4130011 0.0096 303.45 115.8 126.4 1 39,20012 0.0095 268.96 104.8 115.2 1 62,200

Page 82

FILE= WAPAl-l

DATE = 10/6/88

OFFSET = 0.9995

WIDTH = 0.376


NOTES =

% FAILURES ESTIMATEDACCEPTABLE CYCLES TO STRESS


1 377 122.565 4293

10 12564 STODEV50 208709 1.88402277

IALPHA = 360562.30~IBETA = 0.6703826

7.9614E-Q9


cyclest f:'1


SPECIMEN THICKNESS LOAD# INCHES grams o at

1 0.00950 0.6292 111.2 121.8 1 2983,5002 0.00990 0.6971 113.4 123.5 1 22775003 0.01000 0.7141 113.9 123.7 1 97,3004 0.00980 0.6826 113.4 123.6 1 106,1005 0.00980 0.6964 115.7 125.9 1 127,0006 0.00950 0.6199 109.6 120.1 1 133 1007 0.00980 0.6909 114.7 125.0 1 973008 0.01000 0.7154 114.1 123.9 1 100,8009 0.01000 0.7026 112.1 121.9 1 97,300

10 0.00990 0.6792 110.5 120.5 1 10240011 0.00990 0.6759 110,0 120.0 1 102,80012 0.00950 0.6237 110.2 120.8 1 110,600

Page 83

FILE= WAP40-2

DATE = 11/17/87

OFFSET = 0.9995

WIDTH = 0.376


NOTES = (DREW'S CONTROL) - BURR OUT



1 34,718 124.775 40918

10 43,99750 53 198

IALPHA = 55200.457~IBETA = 9.92015694

'-

-2.264E-Q7


cyclesf'

STRESS FEAS S SS

SPECIMEN THICKNESS LOAD# INC SHE JmUlls K I TRE to ad

13 0.0093 264.41 107.5 118.2 1 6380014 0.0093 275.22 113.1 124.2 1 5770015 0.0096 298.06 113.7 124.3 1 5090016 0.0098 309.73 113.4 123.6 1 5230017 0.0097 331.74 124.0 134.4 1 43,70018 0.0098 308.05 112.8 123.0 1 5090019 0.0098 327.35 119.9 130.1 1 4370020 0.0098 302.38 110.7 120.9 1 5800021 0.0099 320.07 114.8 124.9 1 4660022 0.0098 312.50 114.4 124.6 1 5510023 0.0098 314.27 115.1 125.3 1 5590024 0.0097 303.47 113.4 , 123.8 1 52,700

Page 84

FILE= WAP60-1

DATE = 10/5/87

OFFSET = 0.9995

WIDTH = 0.376


NOTES =



1 89,817 129.365 106,969

10 11555250 141418

IALPHA = 147085.85~1BETA = 9.32627928

-7.666E-Q8

AVERAGE AVERAGE0.0022 118.29 129.360

cyclesfail

FEASTRESS

STRESSKSI

SPECIMEN TIllCKNESS LOAD# INCHES grams to

1 0.0093 295.23 120.0 131.2 1 1613002 0.00'93 288.60 117.3 128.5 1 1606003 0.0093 285.38 116.0 127.1 1 1257004 0.0094 304.20 121.1 132.1 1 1299005 0.0094 294.46 117.2 128.1 1 1521006 0.0094 297.96 118.6 129.6 1 1541007 0.0093 296.86 120.7 131.9 1 1456008 0.0093 297.78 121.1 132.3 1 1036009 0.0093 297.86 121.1 132.3 1 158100

10 0.0094 290.24 115.5 126.4 1 10730011 0.0094 291.72 116.1 127.0 1 13060012 0.0094 288.48 114.8 125.7 1 139700

Page 85

FILE= WAP9-l.WQl

OFFSET = 1.1500

WIDTH = 0.376

MATL. = ALLOY 17200 1/4IIT

NOTES = ENDURANCE FINISH



1 23901 135.345 48753

10 66,79250 152,240IALPHA = 178706.67~I

BETA = 2.28657279


SPECIMEN THICKNESS LOAD# INCHES LBS

STRESSKSI

FEASTRESS

cyclesto fail

1 0.0098 0.6504 124.3 135.9 1 3095002 0.0098 0.6669 127.4 139.1 1 3537003 0.0098 0.6642 126.9 138.6 1 1871004 0.0098 0.6238 119.2 130.7 1 861005 0.0098 0.6807 130.1 141.8 1 119,0006 0.0097 0.6271 122.3 134.0 1 1807007 0.0098 0.6477 123.8 135.4 1 1480008 0.0098 0.6543 125.0 136.7 1 1407009 0.0098 0.6855 131.0 142.7 1 183600

10 0.0098 0.6486 123.9 135.5 1 14360037 0.0098 0.6220 118.9 130.3 1 11400038 0.0098 0.6496 124.1 135.7 1 9550039 0.0098 0.6518 124.5 136.2 1 9450040 0.0097 0.6244 121.8 133.5 1 10450041 0.0097 0.6052 118.0 129.6 1 13410042 0.0097 0.6056 118.1 129.7 1 128000

Page 86

FILE= WAP8-1.WQl

OFFSET = 1.15

WIDTH = 0.376


NOTES =

% FAILURES ESTIMATED PEAACCEPTABLE CYCLES TO STRESS


1 37,752 145.265 47,174

10 52.05250 67,339IALPHA = 70799.057~1

BETA = 7.31572949



STRESSKSI

PEASTRESS

cyclesto fail

1 0.0098 0.6855 131.0 142.7 1 835002 0.0097 0.6785 132.3 144.3 1 814003 0.0098 0.7184 137.3 149.1 1 593004 0.0098 0.6854 131.0 142.7 1 698005 0.0098 0.6922 132.3 144.0 1 611006 0.0099 0.6987 130.8 142.4 1 595007 0.0098 0.6939 132.6 144.3 1 630008 0.0098 0.7005 133.8 145.6 1 67600

9 0.0099 0.7103 133.0 144.5 1 5970010 0.0097 0.6751 131.7 143.6 1 7890011 0.0098 0.7211 137.8 149.6 1 5900012 0.0097 0.7084 138.2 150.2 1 56300

Page 87

FILE= WAP61-1

DATE = 10/7/87

OFFSET = 0.9995

WIDTH = 0.376


NOTES =



1 51,292 151.395 59367

10 6332750 74984

IALPHA = 77490.3117 1BETA = 11.1488924

-4.74E-Q9


cyclesf1 '1

FEASTRESS

STRESSKSI

SPECIMEN THICKNESS LOAD# INCHES grams to at

1 0.0098 409.64 150.0 160.5 1 871002 0.0098 382.86 140.2 150.5 1 830003 0.0098 383.62 140.5 150.8 1 765004 0.0098 417.74 152.9 163.6 1 704005 0.0097 397.65 148.6 159.2 1 720006 0.0098 255.37 93.5 103.0 1 638007 0.0098 425.50 155.8 166.5 1 731008 0.0097 404.71 151.2 161.9 1 685009 0.0097 379.50 141.8 152.3 1 72600

10 0.0097 377.61 141.1 151.6 1 6850011 0.0097 383.93 143.5 154.0 1 7190012 0.0097 354.41 132.4 142.9 1 84000

Page 88

FILE= WAP71-1

DATE = 2/15/88

OFFSET = 0.9995

WIDTH = 0.376


NOTES = EQUIP PROB - FAILURE CYCLES APPROXIMATE



1 7,454 166.465 9700

10 10 89750 14776

IALPHA = 15677.3399 1

BETA = 6.18720801-1.193E-Q8 FEA

STRESS STRESSAVERAGE AVERAGE

0.0022 155.23 166.46

cyclesf: '1


SPECIMEN THICKNESS LOAD# INCHES grams to aI

1 0.0094 440.12 175.1 187.3 1 192002 0.0097 437.25 163.4 174.7 1 192003 0.0095 342.69 133.5 144.4 1 13 3004 0.0096 357.71 136.5 147.2 1 14,9005 0.0096 351.81 134.2 144.9 1 13,300

6 0.0094 436.58 173.7 185.7 1 13 3007 0.0096 469.84 179.3 192.3 1 133008 0.0096 430.22 164.1 175.5 1 13,300

9 0.0097 368.92 137.9 148.4 1 13 30010 0.0097 446.15 166.7 178.3 1 13,30011 0.0096 410.49 156.6 0.0 012 0.0096 371.24 141.6 152.3 1 14,900

Page 89

ALLOY 17200 HT

Page 90

FILE= WAPOI-2

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 HT



1 4,888 97.155 41949

10 108,401 STDDEV50 1,300398 2.16661526

ALPHA = 2108674.09BETA = 0.75821538

Calculated FEAStress Stress


SPECIMEN THICKNESS LOAD STRESS FEA cycles# INCHES LBS KSI STRESS to fail

13 0.0098 0.5137 85.3 94.2 1 58050014 0.0099 0.5401 87.9 97.0 1 1044660015 0.0099 0.5445 88.6 97.7 1 64100016 0.0099 0.5357 87.2 96.2 1 36620017 0.0096 0.5335 92.3 101.9 1 32980018 0.0099 0.5467 89.0 98.1 1 280570031 0.0099 0.5534 90.1 99.3 1 1025180032 0.0099 0.5181 84.3 93.1 1 160550033 0.0098 0.5357 89.0 98.2 1 23950034 0.0099 0.5379 87.5 96.6 1 212310035 0.0098 0.5313 88.2 97.4 1 18350036 0.0098 0.5247 87.1 96.2 1 1116500

Page 91

FILE= WAP63-1

DATE = 10/9-10/19/87

OFFSET = 0.9995

WIDTI-I = 0.376

MAIL. = ALLOY 17200 HI

NOTES = TEST TERMINATED 11,303,500



1 100000000 98.215 100000000

10 100000000 STDDEV50 100000000 4.79117576

IALPHA = 100,000,000 IBETA = 9.2100498684846E+161

-1.0857704510611E-17


SPECIMEN nnCKNESS LOAD STRESS FEA cycles# INCHES grams KSI STRESS to fail

1 0.0095 230.76 89.9070564 99.3202425 1 1000000002 0.0093 222.09 90.2908135 99.7991269 1 1000000003 0.0094 229.35 91.2690429 100.835612 1 1000000004 0.0094 236.46 94.0984429 103.89874 1 1000000005 0.0096 233.46 89.0739013 98.377927 1 1000000006 0.0097 224.57 83.9244936 92.7502311 1 1000000007 0.0098 223.04 81.6603175 90.2554759 1 1000000008 0.01 239.27 84.133452 92.8696617 1 1000000009 0.0096 238.63 91.0464536 100.507169 1 100000000

10 0.0096 230.69 88.0170406 97.2328751 1 10000000011 0.0096 224.97 85.8346422 94.8590591 1 10000000012 0.0096 256.71 97.9446638 107.872277 1 100000000

Page 92

F I L E = WAP20-3

OFFSET = 0.9995

"WIDTH = 0.376


NOTES =



1 9,553 106.85 137442

10 446173 STDDEV50 9,723929 1.76599099IALPHA = 17710139'~1

BETA = 0.61131585l.3527E-09


SPECIMEN TIllCKNESS LOAD# INCHES LBS


cyclesto fail

25 0.0098 0.5814 96.6 106.2 1 10000000026 0.0097 0.5850 99.2 1P9.1 1 217860027 0.0098 0.5799 96.3 106.0 1 2,30920028 0.0099 0.5829 94.9 104.3 1 10000000029 0.0098 0.5803 96.4 106.0 1 4,735,70030 0.0098 0.5708 94.8 104.4 1 486960031 0.0098 0.5902 98.0 107.8 1 3,383,20032 0.0098 0.5971 99.2 109.0 1 10000000033 0.0099 0.5862 95.4 104.9 1 122770034 0.0097 0.5684 96.4 106.1 1 5925,80035 -0.0097 0.5840 99.0 108.9 1 429140036 0.0098 0.5972 99.2 109.0 1 3,932,300

Page 93

FILE= WAP18-3.WQ1

OFFSET = 0.9995

WIDTH = 0.376



% FAILURES ESTIMATED FEA -ACCEPTABLE CYCLES TO STRESS


1 132,759 107.15 1006582

10 2,462,544 STDDEV50 25,598,529 1.68309988

IALPHA = 40368663 .1fI

BETA = 0.804605241.0731E-D8

STRESS FEAAVERAGEAVERAGE

97.38 107.1



cyclesto fail ...

25 0.0098 0.5830 96.8 106.5 1 5039,70026 0.0098 0.5799 96.3 106.0 1 10000000027 0.0098 0.5828 96.8 106.5 1 100.00000028 0.0098 0.6022 100.0 109.8 1 100.000.00029 0.0098 0.5832 96.9 106.5 1 7,102,90030 0.0098 0.5916 98.2 108.0 1 671700031 0.0098 0.5989 99.5 109.3 1 10000000032 0.0098 0.5799 96.3 106.0 1 5,50320033 0.0099 0.5930 96.5 106.1 1 543000034 0.0097 0.5708 96.8 106.5 1 10000000035 0.0097 0.5893 99.9 109.8 1 1157490036 0.0098 0.5698 94.6 104.2 I 5,087,200

Page 94

FILE= WAP13-4

OFFSET = 0.9995

WIDTH = . 0.376


NOTES =



1 30,787 115.865 287292

10 770333 STDDEV50 10,179403 1.23083569

IALPHA = 16820029. ~IBETA = 0.72980884

1. 1551E-09STRESS FEA




cyclesto fail

37 0.0098 0.6344 105.4 115.4 1 3464,00038 0.0097 0.6286 106.6 116.8 1 287480039 0.0098 0.6403 106.3 116.4 1 9,90720040 0.0098 0.6302 104.7 114.7 1 4403--,90041 0.0099 0.6421 104.5 114.4 1 10,598,70042 0.0099 0.6468 105.3 115.1 1 3831 10043 0.0097 0.6405 108.6 118.8 1 279570044 0.0098 0.6302 104.7 114.7 1 552450045 0.0098 0.6377 105.9 115.9 1 7915,90046 0.0098 0.6324 105.0 115.0 1 10000000047 0.0098 0.6447 107.1 117.1 1 958800048 0.0098 0.6379 105.9 116.0 1 100,000,000

Page 95

FILE= WAP14-4

OFFSET = 0.9995

WIDTH = 0.376





1 1,192 116.915 28,363

10 114,991 STDDEV50 4,483,647 2.33931439

IALPHA = 9144538.0~1BETA = 0.51424535

2.5317E-08


SPECIMEN THICKNESS LOAD STRESS FEA# INCHES LBS KSI STRESS.. 37 0.0098 0.6712 111.5 121.6

38 0.0097 0.6265 106.2 116.439 0.0098 0.6248 103.8 113.740 0.0098 0.6191 102.8 112.841 0.0096 0.6241 108.0 118.442 0.0097 0.6207 105.2 115.443 0.0097 0.6422 108.9 119.144 0.0097 0.6338 107.4 117.745 0.0097 0.6408 108.6 118.946 0.0097 0.6278 106.4 116.647 0.0098 0.6359 105.6 115.648 0.0097 0.6283 106.5 116.7

Page 96

FILE= WAP64-1

DATE = 10/19/87

OFFSET = 0.9995

WIDTH = 0.376


NOTES =



1 57,146 120.825 98390

10 125,072 STDDEV50 234,361 5.3505737

IALPHA = 264816.89~1BETA = 2.99989947

-3.518E-Q8

STRESS PEAAVERAGE AVERAGE

0.0022 110.26 120.82

cyclesf: '1

STRESS PEAKS I STRESS

SPECIMEN THICKNESS LOAD# INCHES .l!;Tams to aI

1 0.0095 264.41 103.0 113.3 1 2458002 0.0094 303.79 120.9 131.9 1 150,5003 0.0096 298.94 114.1 124.6 1 205,8004 0.0096 268.53 102.5 112.6 1 222,6005 0.0093 270.88 110.1 121.0 1 137,9006 0.0096 297.54 113.5 124.1 1 435,6007 0.0096 277.35 105.8 116.1 1 216,2008 0.0094 289.61 115.2 126.2 1 354,6009 0.0096 282.69 107.9 118.2 1 204,700

10 0.0094 283.26 112.7 123.6 1 19880011 0.0096 283.32 108.1 118.5 1 279,90012 0.0096 286.36 109.3 119.7 1 186,800

Page 97

FILE= WAP28-2

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 H

NOTES = UNHEAT TREATED



1 40675 92.825 47307

10 50571 STDDEV50 60217 7.961641

I:U-PHA= 62297.281 ~I

BETA = 10.7907705-1.926E-08

STRESS KSIAVERAGI AVERAGE

0.0022 84.21 92.82

SPECIMEN THICKNESS LOAD STRESS FEA cycles# INCHES e.rams KS I STRESS tofatl

25 0.0101 246.55 85.0 93.7 1 6610026 0.0102 266.66 90.1 99.1 1 5260027 0.0102 177.97 60.1 66.4 1 52,60028 0.0102 248.25 83.9 92.5 1 5880029 0.0101 256.98 88.6 97.6 1 5810030 0.0101 243.85 84.1 92.7 1 6100031 0.0101 239.12 82.4 -91.0 1 6480032 0.0101 277.65 95.7 105.0 1 46,80033 0.0104 238.61 77.6 85.6 1 6100034 0.0102 262.78 88.8 97.7 1 5430035 0.0104 248.20 80.7 89.0 1 6410036 0.0102 255.40 86.3 95.1 1 56,70037 0.0103 256.39 85.0 93.6 1 58,80038 0.0099 237.72 85.3 94.2 1 56,20039 0.0101 237.36 81.8 90.3 1 56,20040 0.0103 229.62 76.1 84.1 1 5260041 0.0099 268.73 96.4 106.0 1 6960042 0.0103 224.73 74.5 82.3 1 5880043 0.0099 252.81 90.7 99.9 1 6610044 0.0099 239.87 86.1 95.0 1 4880045 0.0101 261.94 90.3 99.4 1 61 10046 0.0101 252.42 87.0 95.9 1 6960047 0.0102 233.56 78.9 87.2 1 6410048 0.0101 248.47 85.6 94.4 1 69000

Page 98

F I L E = WAP28-1

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 H

NOTES = UNHEAT TREATED



1 10,173 125.595 12.228

10 13.262 STDDEV50 16,404 4.38354888

IALPHA = 17096.737~1BETA = 8.86101904

-1.883E-09STRESS FEA


cyclesf: '1


"'-SPECIMEN THICKNESS LOAD

# INCHES grams to aI

13 0.0099 320.47 115.0 125.0 1 1450014 0.0101 333.13 114.8 124.5 1 1450015 0.0104 366.73 119.2 128.3 1 1450016 0.0101 321.98 111.0 120.6 1 16,50017 0.0101 328.85 113.4 123.0 1 16,50018 0.0102 364.67 123.2 132.7 1 14,50019 0.0102 356.40 120.5 129.9 1 1870020 0.0105 357.17 113.9 122.9 1 1650021 0.0105 357.87 114.1 123.1 1 1870022 0.0099 304.87 109.4 119.3 1 1870023 0.0102 367.45 124.2 133.7 1 1150024 0.0099 317.76 114.0 124.0 1 18,700

Page 99

ALLOY 17200 XHM (190)

Page 100

FILE= WAPOI-3

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 (l90)XHM


OBTAIN:1 KSI% FAILURES

1 80,584 88.9250 469,976

STDDEV1.73746366

ALPHA =BETA =

547488.2292.4008691


CALCULATED FEASPECIMEN THICKNESS LOAD STRESS STRESS cycles

# INCHES LBS KSI KSI to fail19 0.01 0.5093 81.2 89.7 1 42620020 0.01 0.5027 80.2 88.6 1 47450021 0.01 0.5049 80.5 89.0 1 41590022 0.01 0.5137 81.9 90.5 1 67520023 0.01 0.5093 81.2 89.7 1 57580024 0.01 0.496 79.1 87.4 1 42680025 0.0099 0.5049 82.2 90.8 1 33190026 0.01 0.5181 82.6 91.3 1 27790027 0.01 0.5049 80.5 89.0 1 39090028 0.01 0.4806 76.7 84.7 1 108700029 0.01 0.4938 78.8 87.0 1 35880030 0.01 0.5071 80.9 89.4 1 373200

Page 101

FILE= WAP65-1

DATE = 10/20/87

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 (190)XHM

NOTES =


OBTAIN KS1% FAILURES

1 121294 95.945 178,282

10 211 338 STDDEV50 329,838 4.01956582

IALPHA = 359676.83~IBETA = 4.23202606

-1.925E-08



# INCHES grams KS I KSI to fail1 0.0096 222.76 85.0 93.9 1 353,9002 0.0096 231.97 88.5 97.8 1 285,7003 0.0096 224.72 85.7 94.8 1 309,9004 0.0095 226.23 88.1 97.4 1 287,7005 0.0095 223.67 87.1 96.3 1 225,8006 0.0096 237.88 90.8 100.2 1 258,6007 0.0096 188.57 71.9 79.5 1 550,3008 0.0096 238.93 91.2 100.6 1 417,8009 0.0096 234.81 89.6 98.9 1 255,800

10 0.0096 227.74 86.9 96.0 1 32070011 0.0096 230.96 88.1 97.3 1 234,40012 0.0096 230.86 88.1 97.3 1 220,00013 0.0096 218.66 83.4 92.2 I 285,70014 0.0096 229.36 87.5 96.7 1 351,50015 0.0096 220.38 84.1 92.9 1 385,80016 0.0096 228.85 87.3 96.5 1 339,40017 0.0096 224.42 85.6 94.6 I 432,20018 0.0096 232.74 88.8 98.1 1 326,70019 0.0096 233.70 89.2 98.5 1 396,80020 0.0096 222.56 84.9 93.9 1 417,80021 0.0096 234.87 89.6 99.0 1 319,90022 0.0096 231.26 88.2 97.5 1 396,00023 0.0096 227.50 86.8 95.9 1 296,20024 0.0096 229.36 87.5 96.7 I 210,000

Page 102

FILE= WAP20-4.WQl

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 XHM (l90)

NOTES =

% FAILURES ESTIMATED FEA

ACCEPTABLE CYCLES TO STRESSOBTAIN KSI% FAILURES

1 45,719 100.225 158,475

10 274,394 STDDEV50 1,154324 1.43148652

IALPHA = 1526583.8~IBETA = 1.31123249

2.7456E-I0



# INCHES LBS KSI KSI to fail37 0.0099 0.5789 94.2 103.7 1 522,60038 0.0100 0.5652 90.1 99.3 1 601600

. 39 0.0100 0.5752 91.7 101.0 1 58010040 0.0100 0.5734 91.5 100.7 1 3,60270041 0.0100 0.5736 91.5 100.7 1 582,70042 0.0100 0.5632 89.8 99.0 1 561,90043 0.0100 0.5641 90.0 99.1 1 1,133,40044 0.0100 0.5583 89.0 98.1 1 642,60045 0.0100 0.5615 89.6 98.7 1 55550046 0.0100 0.5745 91.6 100.9 1 2,406,10047 0.0100 0.5749 91.7 100.9 1 3,694,90048 0.0100 0.5740 91.5 100.8 1 1,839,000

Page 103

F IL E = WAP18-4

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 XHM (190)




1 52,399 104.455 156,328

10 253328 STDDEV50 896072 2.09718519

!ALPHA= 1145743.9~IBETA = 1.49117315

4.3502E-09

AVERAGE AVERAGE94.97 104.45 -"

CALCULATED FEASPECIMEN TIllCKNESS LOAD STRESS STRESS cycles

# INCHES LBS KSI KSI to fail37 0.0099 0.5765 93.8 103.2 1 1,960,60038 0.0099 0.5743 93.5 102.9 1 69960039 0.0099 0.6051 98.5 108.1 1 568,60040 0.0099 0.5839 95.0 104.5 1 2,064,30041 0.0099 0.5853 95.2 104.8 1 2,737,50042 0.0099 0.5784 94.1 103.6 1 601,00043 0.0099 0.5701 92.8 102.1 1 1,190,20044 0.0099 0.5750 93.6 103.0 1 518,00045 0.0099 0.5755 93.7 103.1 1 46220046 0.0099 0.5931 96.5 106.1 1 46600047 0.0099 0.6102 99.3 109.0 1 381,90048 0.0100 0.5877 93.7 103.1 1 629,800

Page 104

a

FILE= WAP14-3

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 HM



OBTAIN KSI, % FAILURES1 144,376 109.85 194,855

10 222,443 STDDEV50 314,573 2.48111896

IALPHA = 336512.999\BETA = 5.43613431

-2.231E-Q9



# INCHES LBS KSI KSI to fail25 0.0100 0.6465 103.1 112.8 1 328,70026 0.0100 0.6134 97.8 107.3 1 282,30027 0.0099 0.6052 98.5 108.1 1 397,90028 0.0100 0.6541 104.3 114.0 1 307,60029 0.0100 0.6094 97.2 106.7 1 309,10030 0.0099 0.6098 99.2 108.9 1 300.40031 0.0100 0.6016 96.0 105.4 032 0.0100 0.6342 101.2 110.8 1 265,50033 0.0100 0.6338 101.1 110.7 1 207,50034 0.0100 0.6411 102.3 111.9 1 282,30035 0.0099 0.6234 101.4 111.2 1 435.60036 0.0100 0.6274 100.1 109.7 1 312,200

Page 105

FILE= WAP13-3

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17200 XHM (190)

NOTES =


OBTAIN - KSI

% FAILURES1 156,289 110.845 224,827

10 263,991 STDDEV I50 401891 2.92912641

\ALPHA = 436132.2~1BETA = 4.48252894

-2.808E-Q8



# INCHES LBS KSI KSI to fail25 0.0100 0.6210 99.0 108.6 1 347,20026 0.0100 0.6372 101.6 111.3 1 377,50027 0.0100 0.6272 100.0 109.6 1 522,10028 0.0100 0.6260 99.8 109.4 1 354,90029 0.0100 0.6276 100.1 109.7 1 513,20030 0.0100 0.6921 110.4 120.2 1 195,60031 0.0100 0.6243 99.6 109.1 1 421,90032 0.0100 0.6354 101.3 111.0 1 522,10033 0.0100 0.6293 100.4 110.0 1 401,50034 0.0100 0.6281 100.2 109.8 1 316,20035 0.0100 0.6368 101.6 111.2 1 522,10036 0.0100 0.6302 100.5 110.1 1 266,500

Page 106

ALLOY 17410

Page 107

FILE= WAP27-1

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17410

NOTES =



I 1065979 47.815 4880,531

10 9,555571 STDDEV50 55449,305 4.30862927

!ALPHA= 78066702.~IBETA = 1.07137935

-4.028E-07



# INCHES LBS KS I KSI tofaHI 0.0099 0.3072 50.0 54.6 1 100,000,0002 0.0099 0.2926 47.6 51.9 1 1,471,0003 0.0100 0.2435 38.8 41.8 1 100,000,0004 0.0099 0.2698 43.9 47.6 1 100,000,0005 0.0100 0.2833 45.2 49.1 1 100,000,0006 0.0100 0.2656 42.4 45.9 1 1000000007 0.0100 0.1978 31.5 33.5 I 100,000,0008 0.0100 0.2787 44.5 48.3 1 14,631,9009 0.0100 0.2512 40.1 43.2 1 713,400

10 0.0100 0.2721 43.4 47.1 1 100,000,00011 0.0099 0.2729 44.4 48.2 1 10000000012 0.0100 0.2736 43.6 47.4 1 100000,00013 0.0100 0.2474 39.5 42.6 1 10000000014 0.0099 0.2842 46.3 50.3 1 100,00000015 0.0099 0.2848 46.3 50.4 1 1 115,80016 0.0100 0.2716 43.3 47.0 1 100,00000017 0.0099 0.2661 43.3 46.9 1 100,000,00018 0.0100 0.3003 47.9 52.3 1 1778,40019 0.0100 0.2793 44.6 48.4 1 10000000020 0.0099 0.2794 45.5 49.4 1 100,00000021 0.0099 0.2695 43.9 47.5 1 1,343,200

22 0.0100 0.2792 44.5 48.4 1 100000,00023 0.0100 0.3032 48.4 52.8 1 10000000024 0.0100 0.3032 48.4 52.8 1 100000000

Page 108

FILE= WAP27-2

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17410

NOTES =



1 2 68.055 220

10 1948 STDDEV50 584091 2.76225904

IALPHA = 1771646.491BETA = 0.33030832

-7.185E-I0



# INCHES LBS KSI KSI to fail37 0.0099 0.3994 65.0 71.7 1 13510038 0.0100 0.3765 60.1 66.2 1 122,90039 0.0099 0.3730 60.7 66.9 1 174,50040 0.0100 0.3810 60.8 67.0 1 100,000,00041 0.0100 0.3721 59.4 65.4 1 143,90042 0.0100 0.3881 61.9 68.3 1 14390043 0.0100 0.3631 57.9 63.7 1 138,80044 0.0099 0.3906 63.6 70.1 1 100,00000045 0.0100 0.3946 62.9 69.4 1 135,10046 0.0100 0.3728 59.5 65.5 1 185,60047 -0.0099 0.4107 66.8 73.8 1 182,50048 0.0100 0.3893 62.1 68.5 1 144,000

Page 109

FILE= WAPI-4

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17410HM



1 26,998 80.3450 95,621-

STDDEV4.17638599

ALPHA =BETA =

106684.0193.34772404



# INCHES LBS KSI KSI to fail37 0.0099 0.4211 68.5 75.7 1 8710038 0.0099 0.4674 76.1 84.1 1 8030039 0.01 0.4431 70.7 78.1 1 8660040 0.0099 0.4167 67.8 74.9 1 10480041 0.0098 0.4343 72.1 79.7 1 9180042 0.0099 0.4123 67.1 74.1 1 9250043 0.01 0.4718 75.2 83.2 1 8030044 0.0099 0.4564 74.3 82.1 1 87900

45 0.01 0.4872 77.7 85.9 1 18050046 0.01 0.474 75.6 83.6 1 8030047 0.0099 0.4255 69.2 76.5 1 10140048 0.0099 0.4784 77.9 86.1 I 86100

Page 110

FILE= WAP57-1

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17410

NOTES =


OBTAIN KSIQ % FAILURES

I 11,341 97.885 31182

10 48742 STDDEV50 156,891 3.9636523

\ALPHA = 196957.5~1BETA = 1.61148642

2.8511E-09



# INCHES l!J'llIllS KSI KSI to fail25 . 0.0099 223.30 80.1 88.5 1 6540026 0.0099 240.99 86.5 95.4 1 95,30027 0.0099 245.69 88.1 97.2 1 144 20028 0.0099 228.32 81.9 90.5 1 11250029 0.0099 241.67 86.7 95.7 I 78,40030 0.0099 237.03 85.0 93.9 1 112,50031 0.0099 243.48 87.4 %.4 I 11250032 0.0099 259.30 93.0 102.4 I 82,40033 0.0099 255.95 91.8 101.1 1 10450034 0.0099 244.54 87.7 %.8 1 65,50035 0.0099 255.29 91.6 100.9 1 109,60036 0.0099 244.86 87.8 96.9 1 7910037 0.0099 256.37 92.0 101.3 1 9920038 0.0099 241.37 95.6 1 311,40039 0.0099 239.89 86.1 95.0 1 311,40040 0.0099 250.93 90.0 99.2 1 127,50041 0.0099 246.27 88.4 97.4 1 311,40042 0.0099 243.80 87.5 %.5 1 311 40043 0.0099 247.90 88.9 98.1 1 311 40044 0.0099 259.80 93.2 102.6 1 112,50045 0.0099 265.90 95.4 104.9 1 123,80046 0.0099 254.49 91.3 100.6 1 311,40047 0.0099 263.90 94.7 104.2 1 522,600

Page 111

F I L E = WAP20-2

OFFSET 0.9995

WIDTH 0.376

MATL. =ALLOY 17410

NOTES =



1 76,252 107.35 94,978

10 104.651 STDDEV50 134,888 2.87540989

IALPHA = 141715.94 1BETA = 7.42215861

-1.1 17E-08


CALCULATED FEASPECIMI THICKN LOAD STRESS STRESS cycles

# INCHES LBS KSI KSI to fail14 0.0099 0.6201 ,. 100.9 110.7 1 117,90015 0.0100 0.6141 97.9 107.5 1 113,90016 0.0100 0.6241 99.5 109.1 1 133,40017 0.0100 0.5918 94.4 103.8 1 151,60018 0.0100 0.5941 94.8 104.1 1 136,20019 0.0100 0.6119 97.6 107.1 1 117,90020 0.0100 0.5869 93.6 102.9 1 169,90021 0.0100 0.6399 102.1 111.7 1 133,40022 0.0100 0.6280 100.2 109.8 1 107,50023 0.0100 0.6073 96.9 106.3 1 151,600

Page 112

FILE= WAPI8-2.

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17410




1 84,069 105.55 104,314

10 114743 STDDEV50 147241 1.67137797

\ALPHA = 154561.013.1BETA = 7.5542714

-1.092E-Q8



# INCHES LBS KS I KSI to fail13 0.0100 0.6078 96.9 106.4 1 106,50014 \ 0.0100 0.5972 95.3 104.7 1 17570015 0.0099 0.6070 98.8 108.4 1 12380016 0.0100 0.5894 94.0 103.4 1 135,100 I

17 0.0099 0.5919 96.3 105.9 1 144,50018 0.0100 0.6033 96.2 105.7 1 151,30019 0.0100 0.6031 96.2 105.6 1 ..14450020 0.0100 0.5831 93.0 102.3 1 17900021 0.0100 0.6012 95.9 105.3 1 15130022 0.0100 0.5954 95.0 104.4 1 172,30023 0.0100 0.6043 96.4 105.8 1 135 10024 0.0100 0.6180 98.6 108.1 1 123,800

Page 113

FILE= WAP13-2

OFFSET = 0.9995

, WIDTH = 0.376

'MATL. = ALLOY 17410

NOTES =



1 41,080.."

109.45 61,921

10 74,223 STDDEV50 119262 3.51117452

IALPHA = 130789.766 1BETA = 3.97224835

-1.071E-Q8



# INCHES LBS KSI KSI to fail13 0.0100 0.6226 99.3 108.9 1 89,20014 0.0099 0.6207 101.0 110.8 1 89,20015 0.0100 0.6247 99.6 109.2 1 103,20016 0.0100 0.6315 100.7 110.3 1 99,10017 0.0099 t· 0.6232 101.4 111.2 1 115,90018 0.0100 0.6378 101.7 111.4 1 99,10019 0.0100 0.5947 94.9 104.2 1 142,50020 0.0100 0.6448 102.8 112.5 1 9910021 0.0100 0.5693 90.8 100.0 1 195,60022 0.0100 0.6400 102.1 JI1.7 1 138,30023 0.0099 0.6227 101.3 111.1 1 13830024 0.0100 0.6387 101.9 111.5 1 119,900

Page 114

FILE = WAP14-2

OFFSET = 0.9995

WIDTH = 0.376

MATL. = ALLOY 17410




1 42,285 112.745 55.514

10 62,606 STDDEV50 85,753 3.20060885

!ALPHA= 91166.16411

1

BETA = 5.9878139-9.08E-09


CALCULATED PEASPECIMEN THICKNESS LOAD STRESS STRESS cycles

# INCHES LBS KSI KSI to fail13 0.0100 0.6208 99.0 108.6 1 99,10014 0.0099 0.6193 100.8 110.5 1 70,50015 0.0098 0.6256 103.9 113.9 1 70,50016 0.0099 0.6045 98.4 108.0 1 110,60017 0.0100 0.6617 105.5 115.3 1 72,30018 0.0099 0.6682 108.7 118.7 1 65,50019 0.0100 0.6384 101.8 111.5 1 72 30020 0.0100 0.6688 106.7 116.4 1 70,50021 0.0100 0.6254 99.7 109.3 I 106,20022 0.0098 0.6185 102.7 112.7 1 9030023 0.0100 0.6638 105.9 115.6 1 87,90024 0.0100 0.6442 102.7 112.4 I 99,100

Page 115

APPENDIX - B

Page 116

ALLOY 17200 1/4HT

FAILURE DISTRffiUTIONS

(CYCLES TO FAILURE vs PERCENT FAILED WITHIN EACH RANGE)

Page 117

ALLOY 17200 1/4HT [3 RUN OUTS]

TEST 03-1 91.7 KSI AVERJ\G!,j: STRESS

,.265,6955,9.tO,865 6,382,475 6,824,085

4,616,0355,057,645

5,499,255CYCLES TO FAILURE

-----r--·--- ------r-------r----- -r--------r---- r------------,

1j

J--I-~ -I -/----f ~

J

II

2~1-1 I 1---1 I f 1--------1!i

o -. (1,.205

3,29 3 732,lS 15 74 425' 4,1,

3(j '," ----·-r --.--.

Z 25

0-'fj-- 2:: 20

.,'¥ 0

r-~

~

;:::;

- '.i) 15-~ Z-,....-~...;J 10-~~.c.t...' 5

ALLOY 17200 1I4HTTEST 01-1 93.2 KSI AVERAGE STRESS

50

Z0 40-'fJ->-- -

..wP

To:

:tl 30

~~- 'fJ

--.c Z-P 20W,..J-~~

10•.ct..'

o

J

:1

682,370 1,415,780 2,149,190' 2,882,600926,840 1,660,250 2,393,660

1,171,310 1,904,720 2,638,130CYCLES TO FAILURE


4,171,1605,077,500

5,983,840CYCLES TO FAILURE

II I + I I + I I +-~-!

1,452,140 2,358,48°3

,264,820

o -

-------r----~-r I I I

45 -j I I-~----I----I----! I I I I I

•

50 -,------r------r--------r ------r

5

Cl 20W.....l.-< 15-<u..l": 10

Z 40o......;2 35>0 30~

::JC/) 25Z......

'":.-~~-.~o

~

1

./if~ '.;;"-"~

~

)

ALLOY 17200 1/4HTTEST 74-1 94.8 KSI AVERAGE STRESS

~,,::,:-~,*",:.•-,. •

.:r'-'~

547,715 . 949,385681,605 1,083,275

815,495 1,217,165CYCLES TO FAILURE

.~

] I I I -I 1·1·1 -=1,351,055

"

~-..;;<~~:,'-;

r-

"I...l••..•~'~.

. ~"""'.'"

)

ALLOYI7200 1I4HTTEST 40-1 95.9 KSI AVERAGESTRESS

..-=~:.:.~--;;- "!\

SO I i I Iii " Iii

I I I I I I45 I I I I,.-,~

~

,.

~~c.~'_ .

o

5

~ 40 I I I I I 11· I I I

"""' I I I I~ 35 I I I I I Ie;.~ 30

rn 25

~~ 20

=::lIS~~.

~ 10

1~

~

~

797,590 . 2,488,660' 4,179,7~0' .1,361,280 3,052,350 ~,420

'·1,924,970. 3,616,040 . 5,307,110CYCLES TO FAILURE

)

•.,

5,870,800

~ .._..~

• J

,..

')

'"

ALLOY 17200 1/4 HT [4 RUN OUTS]TEST·23-1 99.4 KSI AVERAGKSTRESS

~,-,.:;,:r_-<;;-ioi._."._ "=- .\

30 I iii I I I Iii

..

'"

:,.,--~

~".'~~=...:-' .. "

.... '~ -~... ·.P •

"

- - ----

'351'13510'615'12~1,879,1l55,559,165

6,823,155. 8,087,145

CYCLES·TO FAILURE

)

1,767,1953,031,185 295 1754, , .

o

Z 25O.....crn....c •.•e; 20

~rn 15

~Cl

..~ 10

~I:l' 5'~

~~~

~w

.,..."., ..

:\

/'

,

';ALLOY 17200 l/4HT

TEST 23-2 102.7 KSI AVERAGESTRESS..o::-;_~,;;;-->;;.-, ~.-.",

-,,_c"_,' -'".........

J-j

'. ~c,;::.:~.,:"""

;;=~~

N...

10095

90

00 85~

Z 809 75

~ 70e; 65

~ 60

~ 5500 50

~ 45~ 40~ 35

~ 30~ 25~ 20~ 15

105o

'..

, .

I

8 ' ..

0.455.940 0,303.960 0,151.980 100,000,0020,405,280 50,25~,300 80,101,320

30,354,620 60,202,640 90,050,660CYCLES TO FAILURE -

J

"

t'

"...'-~

'\'

- ,e 'II

-------

[....l' --..e---'::-

..

,':,::: ,~

ALLOY 17200 1/4 HT [1 RUN OUT]TEST 23-4 102.7 KSI AVERAGE STRESS

~'~",:;.o~..:;.,.~ ':-"' . \

40 • Iii iii "I ..

~~

Ntil

35 I I I I I I I I I I I

zo~ 30 I~ I I~ I

.~ 25 Ip::l I I;:J I

rF1 20Z I I~ I

~ 15

~

.~ 10

~

5""""'0.,-

o

-...-:~

> •

~ .C5

t'

~~.~.~:C~""

)

. 0,553,4404,062,88016,226,400

18,389,920'\

- I

,,', I ....:.-...._.'

~

-~~ :i.:: -,,,,,

.L

)ALLOY 172~0 1I4-HT [IRUNOU'F]

TEST 23-3 105.9 KSI AVERAGESTRESS..:::-",-~c";_-:_·~

30 I , i I I i • iiiI..

..,.-:~

'I'

.~ .

~:'.~'~;"~.

3,309,5504,085,050

4,860,550CYCLES TO FAILuRE

1,758,550 2,534,050

o

+ " ~+ + ·..·..+..·..·..·..·····..·:.. ·1·..·······..·..·..····:1·'·'···..·..··..·..·'·I·.:.:·:·::~:·~·=.:::~t- ..·.._~ ..·······+ ·..····· ..

Z 25 I Io I I~ I I~ I I..... .

~ 20 I IQ 1 I 1!§ I I I

~ 15

~Q~ ....d 10

~

* 5

?....NQ\

J

l'

l ' "';;' ..--'~--.., .

,:",_: ')

)

-r'-'~

I..

'"

"'.~.

"

~~.'<:~~';'_:', . .- .'

. \

'.,0-.\

ALLOY 17200 1I4HTTEST A2-1 107.4 KSI AVERAGES'tRESS

. ~:'::"f~~~- '/- ,~£

20,129,280 _ 50,080,800 . 80,032,320 .30,113,120 60,064,640 90,016,160

CYCLES TO FAILURE

"

.... .

, '

.....

j

•-.

~~ ~~ ..

0.145.440 0.096.960 0.048.480 .100.000.00

100959085

Z 809 75

~ 70

~65Q 60

E§.55rrJ 50

~ 45Q 40~ 35=30~ 25

Q 20~ 15

10

'5o

~10-0"N~

J

45

.)TEST 20-1

TEST 20-1 112.4 KSI AVERAGE STRESS

<~~::.~"""~- :. \

_....-...•.......•~....,

~......NQO

Z 40'9~ 35

~§30

Cf.) 25

~~ 20~

~ 15

~~ 10

5

. 0248,040

339,380430,720

613,400704,740

.CYCLES TO FAILURE

L

887,420978,760

1,070,100

~-.' - ~

"

Yf~

~c,~~~c:,.;

.\ .

.. ,"

,",,,,;, _:--.~

)

, ....:\-". )

ALLOY 17200 1I4HT'._TEST 13-1 111.9 KSI AVERAGE STRESS

. .c:-~:.~':*- ~.._'~r

30 I I I I i I I I I i

,

:=(JQ~

~

NIC

25 I IZ9~> 20 I ,I~

~r..n 15

~~ •...

~ 10

~~ 5

o, .. 481,780

584,460687,140

,· .. ···....·..·..·······..·1·,·".. ··········..·..·.. ·1

789,820 .. 1,097,860" 1,405,900892,500 1,200,540 .. ,

, 995,180 1,303,220CYCLES TO FAILURE

......~

.,

.~ ....... 1 .-,. . .' .~><-::_~">

)

---'\__ 1

_~c-,-,:.~ __ .-",_

65,80053,110

-,-

40,420

)

\ '~'::';::O'."",*.:

ALLOY 17200 1I4HTTEST 73-1 112.7 KSI AVERAGKSTRESS

31,960 44,650 57,34027,730

o

30 I I I I I I I I I I

~ 25 l ~ I I I I I I I I I ...-•. "

1-01VJ1-01

> 201-01

;p Q(JQ ~I'D~ VJ 15~

~Q

Q~

d 10 I~'I~I I I --I~'<fl I I I I I ~

-<~

~ 5

:""' ....

k

I

.[i

I

_r. . -------,------y.li

)

-,

.:" ,. .)

ALLOY 17200 1I4HTTEST18-1 113.8 KSI AVERAGE-STRESS

~"'::'-~-'.'. \

C:--:0<'~~~""

~:

cfg~....~....

..

20Iii i I I Iii I I

z9 15Cf)

5=)000(

~Cf) 10

~

S~~ 5

~

o390,795 . "1,690,365' '. 2,989,935' 4,289;505

823,985 2,123,555 3,423,1251,257,175 2,556,745 3,856,315

CYCLES TO FAILURE

"

'"C-',,_

..

Of'

·1

.. I·....,l< • __.... :

') t.;I,

lA

ALLOY 17200 1I4HTTEST.14-1 115.3 KSI AVERAGE~STRESS

..-=-"'~~_~~_. _:_ '~r

30 I • I I I iii I i I

i·_._._ _ _ ·1..·· ·1 _._._.- ·1···· ·· ..·..· ·····..1 · ··: 1·..·..· ·..·..·· 1· _ 1 _.- ..I..· · ·..· j1· - 1 _ _ -..I..· ·1 _ J 1 ·..· I· _. _. - · 1· _.1_ ""'''''''-' ·1 ..· _.. _· j

·_·_·_·_· ·..·.._··..· · ·..·_·-..1 ·..·.._·_· ·+· J ..· · ·+ _· ··..· ·+..·..· · 1·_ ·..·..·1- ·_..·..· •..·..· ·..·..·..· ..

~

.-,.-.~ ..

..

~.~~o,'c;:.._~ .. ,>...

·1- · ·..·..· 1..·..·..· · 1..· ·_· · ·..1·..· · + ·' ·1 · ·..· ·_·_..1 _ _ + , j·1 _ ·1·..·..· I ·..·..·_ ·1 ·..1.._· ·..· 1 · · · ·..·..·1 ·..·..· 1..· _·_·..·_..·..1

o

Z25o~ ..

~e; 20

~;:JrJ.) 15

~Q~ ..._..

d 10

~~ 5

1ttl....~

639,220 851,140CYCLES TO FAILURE

286,020356,660

427,300

497,940 709,860568,580 780,500 .

921,780

J

..Jo'-"_."

l""'"~~

i

)ALLOY 172001l4HT

TEST 58-1 116.4 KSI AVERAGE STRESS..\

";;:,""':~~-:c'."'" ~.-, -.~--

.. - ." .

50

45

Z040~

r:J:J;;: 35~

~ 30

r:J:J 25~.

~ 20~

d 15-<~ 10~ ..

5

0200,930 -245,420 - -289,910 - . 334,400

215,760 260,250 304,740230,590 . 275,080 319,570

CYCLES TO FAILURE\

_:,..-~

"

I

._ ....~,'-.

)i -' ,-T


,,::;'"~'-"O_""'-ry;_ ',C·_""

30 I Iii Iii I iii~·······"·"···········:"·I..·..···············C"C"·IC" ···..·,·'·..··I·;·..;·;;··,,,,,·..·..··{···;·..·..·..·,·,,,,'Oc.lo"='o"=o=I='=~·~"7.·,"",I,",",,,··,···,,,··,~'"·~·t~""'''·''·····''·''''I''''''''''·''-·''·-''''i··· I _ ..~ 1 ·1 ..· ·..· 1..· { "'''''' ·1· ·1·..·..·..·· ·..· ·1 · ·..·..·1 ·..·..· I· ·..·..· ·.. j

;p~~

W~

I I25 I IZ9en I' I~ 20 I I

~en 15

~Q , ..

~ 10

~~ 5

o31,280

36,26046,220

1·..·..·..·..· · ·I·..· , ·..·..·..·f · ·..·..·.._.. I· .

·f · ·..·..· ·..·..·I·..·..·_..· ·..·F·..· · ·I"·.. o· .. •••·..,',,· ··I -·..·..· I ··..· ·..·..· ·..~

·f ·..·..·..· ·1·..·..·_ ·1·..· · 1··..·..· ·..·..·I ..· · · I..·..· ·..·..·..·..· ~

51,200'" 66,140

.C-'''~

~.

'"

.~c ..~.~,,;~.;

41,240 56,180 71,120CYCLES TO FAILURE

~,'

I (~

')

~

,.

.,....,;:<--

t'

cr~c~"-'"

. ALLOY 17200 1/4HT.TEST.A1-1 122.5 KSI AVERAGESTRESS

\.z;;:;.,,..,-t;- ~._ ' .•.r " . -~.- ..

~ -100

9590

Z 85o 80~ 75~ 70

~ 65.

~ 6055

00 50

2S 45~ 40r;il 35

=:I 30

~ 25

~ 2015

10.........~.. _.

-50

241,610 1,107,470 1,973,330530,230 1,396,090 2,261,950

818,850 1,684,710 2,550,570CYCLES TO FAILURE

-----~

"'C

~~

t..H!.II

(.

+····..·..···············1·..•..•·•··•········..·..··+..····· + _ + _ ····1··..·..·_········ ..····+..·..·..··:············ .. ··1···· + + _ .,.-,.:-

-I

~:."~~.""

....,.\. ~--"~'

.......~ ..

63,800

61,790 .59,780

I··I·~-~--+ .._-----...·__._-

57,77053,750

55,760CYCLES TO FAILURE.

51,740

49,730

(").

)

ALLOY 17200 1I4HTTEST 40-2 124.8 KSIAVERAGE:STRESS

..0:--.1"..".;:;:-..;._.:.;.....""" .

47,720

o.. 45,710

20 I I I I I I I I I I

zsa ISrJJ

>l-olQ

~rJJ 10

~

~~ 5

~

[

1~....C.NQ\

.._ ;l'··

/---..,'~:::-._::)

)

ALLOY 17200 1I4HTTEST 6Q~1 129.4 KSI AVERAGE STRESS

C.=f'.;O;;:;;:;;'- ~'.'-"'-

30 I I I I I I I I ..~ I I I

-1- , ·······················1······················1·······....•..._•....-1-.-·__·····-(··_·············..·..1 ··'··· · ···1·····.."" "."••••.~ ..-I- ·..·······..1· ···1..·..······•····•·•··..·1···········:··..··..··1············ ······1····· ··..·..·..···1····..··· ·········1·..················,..I······················j-1-········..···..·······•···..··..······..······1 ......··..······..··....·1..·..············_....1..······•···•·•····..···1··········..··....;···1·······....··..····..···1·····..·..·..·········1·..··..······_·······..·····················

;:t;-

.. -;;

..' ..

.~C'~'~·"'"

':r

129,565 146,875135,335 152,645

CYCLES TO FAILURE118,025

112,255106,485

o

25Z -1-······.. ·.... ·.·..•·....·..·..·..·..·....·1···..·······..·..····..19i20 1-="=1,,,,-'='1=-',.,=-1..-:.'---=1.---,.-.-1.::.:-.:.:.:.l :..-k.::::::::I:::.==.t

t/) 15

~

~ 10

~~ 5

~~~

w.......

)'...,:....., .

.,--.:~

~

+..···· ..·,..· · _·.-·_ ·.._..·..·_· 1- ·· ·..·..· 1····· ..·· ·..·..·.._..1 ·..·..·..· · 1· · ·1·..· · ·· ·..·1· ..·..·· ·..·..·..·..· · ·..· ·_..·_·I ·..·..·..· ·j

"",

"'-.~'"

"

~c.~s.:<......·.

340,320

\

260,040206,520 286,800

1· ..· .... ··..· .. ·1 .......... ·······1..·.... ···+· .... ··..·.....

·l ·..·..·_..··· I== ·.. ··.· L·_· ··..· _·J...· · :: =..:l=..· ·..·..·..·..·L ·..· · ·j

. 233,280 313,560CYCLES TO FAILURE

179,760

·1 ·..·..·.._·..· ·1 · ·..·..· · 1·..·..· ··..1·..·..·..·;· ·1 · ·..· ·..- ..·~· I ·..·..·..· ·.. j

153,000

·1 ·..·..· 1· · ·..·..·..·..·..·+· ·..·..·..· ·1· ..·..·..·..· · ·1·..·..· · ·..·..·1-..· · ··..·..·1 ·..· ·1 · ·..·_..· ..

ALLOY 17200 1I4HTTEST 9-1 135.3 KSI AVERAGlt' STRESS..,::-",-..;-.,;:;;--..;.--:-"""

126,240

30 I I i I I I I I I' I I

Z 2S

9rr.J~

;;> 20~

~rr.J 15

~Cl "...

~IO~ 5

1ttl

"""~QC

. -(

r-~.l

..........;,r-..

....--.. .

\~)

)

ALLOY 17200 1I4HTTEST8-1 145.Z",KSI AVERAGE sTREss

~-'.-

65,826

-~.._." .. - .-

73,98668,546 76,766

"'-..

82,146 '.

.-'~

".

.,.

~i.<i.~::~_C~

.-,~J

')

ALWY 17200 1I4HTTEST 61-1 151.4 KSI AVERAGKSTRESS

~;:--.,:;.~.!.~~

.,~

".

----. ~c-'~~:';c,:

71,955 78,94574,285 81,275

85,935

76,615 83,605CYCLES TO FAILURE

) .

r:........l )

/"",,.'j

._~.~- .. ~~,;i..:~."'; ...·-:,.-.-_

<'1

)ALLOY 17200 1I4HT

TEST 71-1 166.5 KSI AVERAGE STRESS..:F-";<;;:"~~-".;·

:.--,i,;~

.;

18,905

18,31517,725

, 17,13515,955

16,545CYCLES TO FAILURE

15,365

14,775·14,185

13,595

~~l_1 I I I I I I I I· It:: 50

~ 45

~ 40

~ 35

~ 30

=:::l25~ 20

~ 15

10

5

o

1('D..."""...

statistical failure analysis of copper beryllium strip

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