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UNCLASSIFIED AD 2 7 7 487 ARMED SERVICES TECHNICAL INFORMATION AGENCY ARLINGTON HALL STATION ARLINGTON 12, VIRGINIA UNCLASSIFIED

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Page 1: ARMED SERVICES TECHNICAL INFORMATION AGENCY … · minutes, followed by a wipe with cheesecloth. After fin-ishing was completed specimens were subjected to a total of 168 hours by

UNCLASSIFIED

AD277 487

ARMED SERVICES TECHNICAL INFORMATION AGENCYARLINGTON HALL STATIONARLINGTON 12, VIRGINIA

UNCLASSIFIED

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NOTICE: When government or other drawings, speci-fications or other data are used for any purposeother than in connection with a definitely relatedgovernment procurement operation, the U. S.Government thereby incurs no responsibility, nor anyobligation whatsoever; and the fact that the Govern-ment may have formulated, furnished, or in any waysupplied the said drawings, specifications, or otherdata is not to be regarded by implication or other-wise as in any manner licensing the holder or anyother person or corporation, or conveying any rightsor permission to manufacture, use or sell anypatented invention that may in any way be relatedthereto.

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REPORT NO. FGT-2926DATE: 1 June 1962

_.J

I PROCESSING - CONVENTIONAL CHROMIUM PLATEON HIGH STRENGTH STEEL - CORROSION RESISTANTFLUID APPLIED TO - EVALUATION OF

IIIA

JUL9 1962IH l . -. - /' , A I

U LL~LZU La.ISIA 0

Published and DistributedUnder Contract No- AF33(657)-7248

CGENERAL DYNAMICS I FCORT WORTH

..|'i]•

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Dep~rtmen fCONVAIR D'-.p"tm.

C 0 N V A RFWP I?"9-S44

A DIVISION OF GENERAL DYNAMICS CORPORATION

(FORT WORTH) __

TEST NO. 50-1151 : REPORT FGT-2926

MODEL B-58 DATE 13 Feb. 1962

TITLE

PROCESSING - CONIENTIONAL CHROMIUM PLATE ONHIGH STRENGTH STEEL - CORROSION RESISTANT

FLUID APPLIED TO - EVALUATION OF

SUBMITTED UNDERContract NT umberAF33 (600) -38975

Tests were conducted from26 Feb. to 15 Dec. 1961.

PREPARED BY:_____________ GROUP: C- Cem'"istry Lab.E. W. Turns Ensineerirn Test Laboratories

_.... . . REFERENCE: FGT-2732

CHECKED BY:-C EV-L APPROVEDBYC. E. Miller K.E. Zorcas

NO. OF PAGES _______

NO. OF DIAGRAMS______TT-. . ,•isoF

REVISIONS

NO. DATE BY CHANGE PAGES AFFECTED

Ei _ _ _ ____ _

_ __ _ _ _ _ _ _ _ _ _ _ _ _ _ -

-

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NV REPORT NO FT- 296A DIVIlON OF GENERAL DYNAMICS CORPORATION MODEL B-58

(FORT WORTH) DATE 2--62

PROCESSING - CONVENTIONAL CHROMIUM PLATE ONHIGH STRENGTH STEEL - CORROSION RESISTANT

FLUID APPLIED TO - EVALUATION OF

PURPOSE:

CF-500 crack-free chromium possesses good corrosionresistance with normally thin plating, an equal thicknessof conventional chromium electroplate with its inherentfine microcracks is inadequate as a direct substitute.This test was performed primarily to determine if conven-tional chromium electroplate in..0020" - .0025" thicknesscould be used in lieu of CF-500 provided it received addi-tional treatment for improved corrosion resistance.

A second problem involved the development of a test todetermine whether parts have CF-500 chromium or conventionalchromium electroplate.

The purpose of this test, therefore, is to invesigateseveral materials for improved corrosion protection and todevelop tests to differentiate between CF-500 and conven-tional chromium electroplate,,

SUMMARY:

Three types of tests were conducted in the EngineeringChemistry Laboratory. A summary of the test procedures,results and conclusions follow:

I Tests to determine the effectiveness of DC-15A (DCF-15A) and G. E. material number 514-1789-6 as corro-sion inhibitors for inadequate thickness of conven-tional chromium electroplate.

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PAGE 2

C 0 N V A I R REPORT NO Iz2)26

A DIVISION OF GENERAL DYNAMICS CORPORATION MODE' B-58

(FORT WORTH) DAT E -13-62

Specimens of H-1 type steel were plated with .002"--.00251" conventional chromium electroplate fromeither a 33 or 53 oz/gal plating solution. A segmentof the specimens were exposed to MIL-F-5566 anti-icingfluid to simulate a service condition. All specimensincluding controls were exposed to 20% salt spray byprocedures described in Federal Test Method Standard151, Method 811 for 48, 120 and 168 hour periods.Corrosion began at approximately 90-120 hours and haddeveloped appreciably by 168 hours. An identicalthickness of CF-500 crack-free chromium would pass250 hours of salt spray with no corrosion. On thisbasis it was concluded the corrosion Inhibitors wereinadequate.

II Tests to differentiate between CF-500 and conventionalchromium electroplate.

Six different methods were investigated for distinguish-ing or determining the extent of cracks in chromiumelectroplate. I'; was concluded that only one method,the electrolytic copper sulfate test, was effective inaccentuating cracks and differentiating between the twochromium electroplates.

III Tests to determine the effects of corrosion inhibitorson simulated hinge pin bearing surfaces.

Standard test races were lubricated with X-38 dry-solidfilm lubvicant and installed on a modified MacMillanlubricant wear test machine. Test corrosion inhibitorswere dropped on the race while oscillation was in pro-gress. A marked decrease in hours wear life was notedand it was concluded the fluids were detrimental.

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PAGSC 0 N V A I R REPORT No'FGT'2926

A DIVISION OF ONERAL DYNAMICS COIPOIATION MODEI ., B- 2(FORT WORTH) DATE 2-i3-62

PROCESSING - CONVENTIONAL CHROMIUM PLATE ONHIGH STRENGTH STEEL CORROSION RESISTANT

FLUID APPLIED TO - EVALUATION OF -

OBJECT:

1. To determine the degree of improved corrosion protectionafforded conventional chromium electroplate by Dow-Corn-IngDC 15A or General Electric's material Number 514-17n -6. o

2. To develop tests to differentiate between CF-500 andconventional chromium electroplate.

3. To determine the effects of improved corrosion resistanttreatments on simulated hinge pin bearing surfaces.

SPECIMENS, MATERIAL AND TEST EQUIPMENT:

I Specimens

Item Use Source

15 pieces 2"x5"x Basis metal for Universal Cyclops Corp..040" H-11 steel salt spray test Stewart Street

specimens Bridgeville, Pa.

1 piece 1/2" x 3" Basis metal for Universal Cyclops Corp..040" H-11 steel salt spray test Stewart Street

specimens Bridgeville, Pa.

1 piece 2"x2"x Basis metal for Universal Cyclops Corp..040" H-Il steel salt spray test Stewart Street

specimens Bridgeville, Pa.

21 pieces 1-1/2" Basis metal for Universal Cyclops Corp.x 3"x.040" H-il orack detection Stewart Streetsteel tests Bridgeville, Pa.

42 standard test Bearing test Timken Roller Bearing Co.races No. T surface Toledo, Ohio54148 Code 3-223

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PAG3 4ICONVAIR NO

"~~ 0|A NO,.FT V9 A

A DIVISION OFNGIERAL DYNAMICS CORPOATION MODEL B-58(FORT WORTH) DATE 2-13-62

II MaterialsItem Use Source

15 gallons of 33 Application of Solvay Process Divisionoz/gal conven- conventional Allied Chemical Corp.tional chromium chromium plate 61 Broadway

Splate solution to test speci- New York, N. Y.men

15 gallons of 53 Application of Solvay Process Divisionoz/gal conven- conventional Allied Chemical Corp.tional chromium chromium plate 61 Broadwayplate solution to test specimen New York, N. Y.

15 gallons of 44 Application of Metal & Thermit Co.oz/gal CF-:.. . crack-free Rahway, New Jersey500 plating chromium platesolution

1 pint of Dow Test corrosion Dow Corning Corp.CorningFiSA Cor- inhibitor 592 Saginaw Roadrosion inhibitar Midland, Michigan

1 pint of General Test corrosion General Electric CompanyElectric corro- inhibitor 1 River Roadsion inhibitor Schenectady 5, N. Y.No. 514-1789-6

1 quart of Parco Bearing race Parker Rustproofing Co.Lubrite No. 2 pretreatment 2169 East Milwaukee Ave.MIL-C-16232 Typel Detroit 11, Texas

1 quart of Test contami- Union CarbideUcon Fluid nant for bear- 30 East 42nd St.

ing surfaces New York 17, N. Y.

1 quart MIL-L- Test contami- Shell Chemical Company60 5 oil nant for bear- 308 Madison Avenue

ing surfaces New York

1 gallon of Iso- Test contami- Fisher Scientific Companyropyl alcohol nant for bear- 203 Fisher BuildingMIL-F-5566) ing surfaces Pittsburgh 19, Pa.

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PAG0 5C ON V A I R REPORT NO- 6A DIVHMON OF @ENEA DYNAMICS COROIATWO MODEL

(FORT WORTH) DATE- -13' t'

4

111 Equipment

ben.. Use Source

Heat treat furnace Heat treating Hevi-Duty Electric Co.of basis metal Milwaukee, Wisconsinspecimens

Vapor honing Application of Reumelin Mfg. Co.apparatus electroplates Milwaukee, Wisconsin

and anodictreatments

Salt spray chamber Application of Industrial Pump & Filtertest environ- Manufacturing Companyment

Hydraulic Press Application of American Instruments Co.Uniform Pres- Silver Springs, Md.sure to crackdetection testspecimens

Research Metallo- Examination of Bausch & Lomb Companygraph crack detection 626 St Paul Street

test specimen Rochester 2, N. Y.

Binocular Micro- Examination of Bausch & Lomb Companyscope crack detection 626 St Paul Street

test specimen Rochester 2, N. Y.

XacKillin, Lubri- Testing wear Hartman Tool Mfg. Co.cant wear test life of finish- Los Angeles, Calif.machine ed races

PROCEDURES:

Part I - Improved Corrosion Resistance Test

Specimens requiring conventional chromium electroplate wereplated as indicated from either a 33 or 53 oz/gal chromiumtank containing SO4in as H S0 4 in a ratio of 1/100 S08, to100 parts chromic acid. The tank temperature was 130 t5*Fand the plating current density was two amps/inch square.Plating thickness was .0020 to .0025".

All basis metal specimens were heat treated to a 250,000-280 000tensile ultimate strength level and vapor honed to remove aliheat treat scale.

-- -- -- 1

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PAOL 6C CON VA IR RPR NO- 2rTP2&A DIVISION OF GENERAL DYNAMICS COIRPOATION MODEL 1-58

(FORT WORTH) DATm 2-13-62

CF-500 crack-free chromium electroplate was applied froma solution containing 44 oz/gal of CF-500 powder. Theplating current dens.ty was 2 amps/inoh square while thetemperature was 150 7-20F. Applied plate thickness was.0020"- . 0025".

Specimens requiring treatments with the special corrosioninhibitors were dipped in the test corrosion inhibitorsfive minutes and wiped dry with cheesecloth. The soakin MIL-F-5566 (iso-propyl alcohol) fluid was for 15minutes, followed by a wipe with cheesecloth. After fin-ishing was completed specimens were subjected to a totalof 168 hours by procedures shown in Federal Test MethodStandard 151, Method 811 for 20% salt spray.

Part II - Development of Methods for Crack Detection Tests

A. Modified Ferroxyl Test

A solution composed of 10 grams agar, 10 grams sodiumchloride, 1 gram of potassium ferrocyanide and dis-tilled water to make one liter was made up. Thesolution was warmed and the chromium plated specimenswere dipped in the solution for 3-5 minutes. Speci-mens were removed and allowed to dry in the horizon-tal position. The specimens were examined for aTurnbulls blue appearance in voids, cracks, etc..

B, Electrolytic Copper Sulfate Test

A solution was prepared containing 200 grams of coppersulfate, 75 grams of sulfuric acid added to sufficientwater to make one liter. The test specimen was madethe cathode in the solution for 1 - 2 minutes using acurrent of approximately 3 amps/ft square. Specimenswere rinsed, dried and examined at 25, 150 and 250power magnification for crack identification.

0. Salt - Peroxide Test

A solution was prepared containing 5.8 grams of sodiumchloride.3 cc's of 3.6Vhydrogen peroxide in one literof water. Test specimens were soaked in the solutionfor 4 hours, removed~rinsed and examined for cracks,

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PAG 70 N V A I R REPORT NO

A DIVISON OF GNNRAL DYNAMICS CORPOLATION MODEL B-'

(FORT WORTH) DATE P-1 •-

D. Electrographic Test

A solution was made up with distilled water using5% sodium carbonate and 1% sodium chloride and asmall amount of potassium ferrocyanide. This solu-tion was used to saturate a firm type filter paperwhich was inserted between a test specimen and analuminum plate. A hydraulic press was used toapply a pressure of up to 100 psi to the assembly.The test specimen was made the anode while thealuminum plate was made the cathode. A 3 voltpotential was applied for 15 to 20 seconds. Thespecimen was examined at various magnificationsfor cracks.

E. Anodic Chromic Acid Test

A test coupon was made the anode in a 33 oz/galchromium plating solution at 2 amps/inch square for2 to 5 minutes. At that time the specimen wasrinsed and examined at 25, 150 and 250 X magkhifica-

* tion for cracks.

F. Ferroxyl Test

A 25% rag bond paper was coated on one side with adistilled water solution containing 50 grams/litersodium chloride and 50 grams/liter agar agar andallowed to dry. At the time of test the paper wasdipped into a solution of 50 grams/liter sodiumchloride and applied to specimen with the agar sidecontacting the specimen. The paper was kept moistwith the sodium chloride solution. After fiveminutes had expired the paper was dipped into anaqueous solution of 10 grams/liter potassium ferrn-cyanide. The dried paper was examined for bluespots, indicating contact with and corrosion of thesteel.

After the various crack detection tests had been appliedto test specimens they were visually inspected on asterioscopio microscope at 7 to 30 power magnification.Specimens were then examined on a metallograph at 150and 250 magnification for crack definition and accentu-ation. Photomicrographs were made at significant inter-W2s of magnification.

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t8-i FAGS

CO0NV A IR RIOTNO GA DIVISION OF GENERAL DYNAMICS CORPORATION MODI B'-58

(FORT WORTH) 2, _-i -62

Part III. Tests to Determine the E'ffects of Corrosion

"Inhibitors

A. Preparation of Test Races

1. Standard test races (Timkein Roller Bearing Co.,No. T 54148 Code 3-223) wex'e grit blasted to amatte finish using 120 meski aluminum oxide grit.

2. After grit blasting the rares were wiped inclean methyl ethyl ketone •and vapor degreasedin hot vapors of trichloro-ethylene. From thispoint on races were handled.wLthL;clean cottongloves.

3. After cooling to room temp-erature the races werepretreated in a solution o f Parco LubriteNumber 2.

4. After pretreating, the rac es were rinsed in hotrunning water and dried in a 160*F oven for 30minutes.

5. When cool the races were nmeasured to the near-est .00011' and the measurem.ent recorded.

6. The races were then placed- on a rotatingspindle and sprayed with t-he appropriate solidfilm lubricant.;

7. The solid film lubricant c oatIng was cured by,oven baking at various temaperatures to promotethe curing action.

8. Dimensions were checked a;ain after the curecycle was complete and them race was cool todetermine that the correct thickness .0003" to.0005" had been applied.

B. Testing of Races

1. The races Goated with soll.d film lubricant asdescribed above were tested on a modified Mac-Millan lubricant wear test-.machine operatingin a 22.5* angular oscilllting motion whileunder a 63,000 psi load.

UTILITY REPORT SHUET ope#p ~ 4PWP 1072-.44"

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PAGE

"" 0ON V A IR REPORT NO1O2B

A DIVISION OF OGNERAL DYNAMICS CORPORATION B-58(FORT WORTH) DATE 2-13-62

2. As denoted in Table I a new race was used witheach fluid tested. The rub shoe block waschanged for every teut using a new polished rubshoe each time. The fluids were dropped ontothe coated test race with new dropping pipettesso that the fluid would be in the contact areaof the rub shoe and the rub shoe was subse-quently lowered onti the race.

S3. The machine was started and a one pound weightwas added every 60 seconds until a total oftwenty weights had been applied to the bail rod.Running time of machine was calculated from the"initial start until failure, determined by auto-matic stopping of the machine by a switch trig-gered by sufficient increase in the coefficientof friction. Wear life was determined to thenearest 0.1 hour.

( 'RESULTS:

Table I shows the effects of various materials on the wearlife of test races.

The effects of 48,120 and 168 hour salt spray on test fin-ishes are shown in Figures 1, 2 and 3. Figure 4 is aphotomicrograph of conventional (cracked) chromium electro-plate while Figure 5 shows the normal uncracked plate ofCF-500 chromium. Figure 6 through 12 show the results ofmethods A through F tests to develop crack detectionmethods.

DISCUSSION:

A situation had developed where the substitution of .0020"-.002$" of conventional chromium electroplate for an equalthickness of CF-500 chromium was virtually mandatory. Itis known that ordinary chromium plate has many microcracksand is, therefore, only fair in corrosion resistance. Asearch for a wipe on or brush applied corrosion inhibitorwas begun in order to improve adequately the corrosionresistance of conventional chromium electroplate.

4

4

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APAGE 10SC 0 N V A I RREPORT

A DIVISION OF OENERAL DYNAMICS CORPORATION MODE B(FORT WORTH) 2-13-62

The two materials selected and tested were Dow Corning15A and General Electric's material #514-1789-6 fluids."Since planes in service are occasionally flushed with"anti-icing fluid a fifteen minute immersion in MIL-F-5566 anti-icing fluid, Just prior to salt spray exposure,was added. In Figures 1, 2 and 3 it is evident that bothinhibitor test fluids extend the corrosion resistance butminor corrosion occurs in 120 hours and extensive corro-sion is prevalent at 168 hours. The immersion in anti-

* icing fluid obviously decreased the corrosion resistance.It is interesting to note that an equal thickness of CF-500 chromium electroplate (without the anti icing fluiddip) withstands 250 hours of salt spray as illustrated inFGT-2732.

A second problem was the identification of parts inorder that those having conventional chromium might beadequately treated. FAgu.cS 4 through 12 are micro-photographs of specimens after certain crack detectiontreatments. Figures 7 and 8 are different magnificationsof cathodic treatment in copper sulfate plating solution.Note that cracks in basis conventional chromium platedH-11 steel are all identified and accentuated by thestringers of electroplated copper metal. It was surmisedthat the basis metal, H-11 steel, being more conductivethan the conventional chromium electroplate allows segre-gated plating only at cracks where solution wicks throughto basis metal. Crack definition and accentuation withthis method was superior to others tested. It was theonly method developed that appeared to show all cracks.

Being able to apply this inspection type test by brushplating techniques would be very desirable from a prac-tical, low cost standpoint. Efforts were made to developa brush type test but they were largely unsuccessful.

A third problem was the effects of the corrosion inhibi-tors on the wear life of bearing surfaces simulated bytest races as shown in Table I.

It is obvious that all materials tested reduced the wearlife to a considerable extent. Materials such as UCONoil, MIL-L-6085 oil and anti-icing fluid were added be-cause they are likely contaminants.

II

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PAr, 11

C ON V A I RtEPORT NO FGT-2925A DIVISION OF OENERAL DYNAMICS CORPORATION MODEL

(FORT WORTH) DATE 2-13-62

1. Very slight improved corrosion resistance can beexpected from the use of DC-15A or GE 514-1789-6corrosion inhibitors. The advantages are incon-sequential.

2. A test to distinguishýbetween CF-500 crack-free..and conventional chromium plate was developed.

It is the method B, electrolytic copper sulfatetest.

3. Test corrosion inhibitors diminished appreciablythe wear life of bearing surfaces.

61711 ow 6f

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'A ' ,, 12

C 0 N V A I R REPORT N C:___926& A DIVISION OF GENERAL DYNAMICS CORPORATION MODE, 3-52

(FORT WORTH)4

TABLE I

EFFECTS OF VARIOUS FLUIDS ON WEAR LIFE OFSIMULATED HINGE PIN BEARING SURFACES

Test Conditions

Test Machine - MacMillan Wear Life TesterLoad - 63 000 psiSpeed - 240 cycles per minuteAngular Oscillation - 22-1/2°

Specimen Lubricant Results-Number Applied'* Test Fluid HourS. Remarks?

1 X-38 None 14.2 Controls2 X-38 None 20.4 Controls3 X-38 None 19.4 Controls

4 X-38 DC-15A 0.4 Test Fluid5 X-38 DC-15A 0.4 Test Fluid

6 X-106 DC-15A 0.2 Test Fluid

7 X-38 UCON 0.5 ContaminantFluid

8 X-38 UCON o.4 ContaminantFluid

9 X-lo6 UCON 3.4 ContaminantFluid

10 X-38 MIL-L-6085 oil o.6 ContaminantFluid

11 X-38 MIL-L-6085 oil 0.6 ContaminantFluid

12 X-38 MIL-F-5566 3.8 ContaminantFluid

13 X-38 MIL-F-5566 2.5 ContaminantFluid

UTILITY REPORT SHEET OpetnInt

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oPAG

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i~'GT2 26 PAGE 15

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tS~ I' rS U a~REPORT Gr~ ~ " ~ , ~.MODEL,~

(FORT WOJRTH) DATE--------

'ICMAEJ3 4

~cnvn~jra ,ri~elec tr;Pa -%c show -Ing 25ox

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CO0N V A IR EOYOFjZA WAWNC Of GOWAL DYNAMICS COISPOIAT ION MOOEL &

~c r rve:r

Methý)d B, e1*cti'olytic uOpper .,ilfaltetest applie~d to conventional c~riael~c~txroplate - 25y

ROMP V "

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CO0NV A IR REPORT~

A DIV?5ON Of GIN(RfM DYNAMICS (C2OItOAYION

(FORT WORTH) DATELL

a,0 250Xrt~ 'L

U.,

-J Method C, salt-peroxide test, applied to&cwentional chromium~ electroplate - 250X

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7~ 'osozy tctsapplied o'unVeLC~xM2Ce 2;:ir-: cc-opla te 2 250X

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