me 231 · 02/07/2014 · title: me 231 author: darrell socie created date: 4/18/2012 3:44:09 pm
TRANSCRIPT
![Page 1: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/1.jpg)
Cast Iron Fatigue
Professor Stephen D. Downing
Department of Mechanical Science and Engineering
University of Illinois at Urbana-Champaign
© 2011-2012 Stephen Downing, All Rights Reserved
![Page 2: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/2.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 1 of 45
Outline
1. Comparison to Wrought Metals
2. Conceptual Models
3. Stress-Strain Behavior
4. Fatigue Behavior
![Page 3: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/3.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 2 of 45
Cast Iron vs. Wrought Steel
Cast iron is a composite material
Steel matrix
Graphite particles of different shapes
Graphite makes cast iron
More prone to surface cracking
Stiffer in compression than tension
New methods need to account for
differences
![Page 4: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/4.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 3 of 45
Nodular Iron
Spheroidal graphite
Fairly consistent size
Behavior similar to steel
Gray Iron
Graphite flakes
Behavior very different
from steel
Compacted Flake Iron
Intermediate behavior
Microstructure
![Page 5: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/5.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 4 of 45
Strain-Life – Wrought Metals
Major Assumptions:
Local stresses and strains control fatigue
behavior
Accurate determination of Kf
![Page 6: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/6.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 5 of 45
Similitude
Plastic
Zone
Ds , De
Ds , De
DS Nominal stress
![Page 7: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/7.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 6 of 45
Fatigue Analysis: Strain-Life
Material
Data
Component
Geometry
Service
Loading
Analysis Fatigue
Life Estimate
eN curve
se curve
Kf
DS , Sm
![Page 8: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/8.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 7 of 45
Cyclic Hardening / Softening
![Page 9: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/9.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 8 of 45
Stable Hysteresis Loops
2,
sDs
2,
eDe
Ds
De
![Page 10: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/10.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 9 of 45
Stable Hysteresis Loops
2
sD
2
eD
![Page 11: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/11.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 10 of 45
Strain-Life Data s - e
0
100
200
300
400
500
600
0 0.004 0.008 0.012
Strain Amplitude
Str
ess A
mplit
ude
De Ds Ds
2 2 2
1
E K
n
'
/ '
During cyclic deformation, the material deforms on a path
described by the cyclic stress strain curve
![Page 12: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/12.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 11 of 45
Cyclic Stress Strain Curve
![Page 13: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/13.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 12 of 45
Stable Hysteresis Loop
Ds
De
Dee Dep
Hysteresis loop
Cyclic se
Masing behavior
Symmetrical
![Page 14: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/14.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 13 of 45
Strain-Life Data De - 2Nf
10-5
10-4
0.001
0.01
0.1
1
Reversals, 2Nf
Str
ain
Am
plit
ude
100 101 102 103 104 105 106 107
c
f
'
f
b
f
'
f )N2()N2(E2
es
eD
c
b
'
fe
E
'
fs
2Nt
2 Reversals, 2Nf = 1 Cycle, Nf
![Page 15: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/15.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 14 of 45
Cyclic Deformation
A
C
B
D
E
F
G
H
I
B
D
A, I
C
E
G
H
F
str
ain
Loading history Stress-strain response
![Page 16: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/16.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 15 of 45
Neuber’s Rule
eDsDDD eSK f2KT S
KT e
s
e
se KKKT
![Page 17: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/17.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 16 of 45
Mean Stresses
s
e
smax
De
Smith Watson Topper
cbfff
bf
f NNE
ess
eD
s )2()2(2
''2
2'
max
2max
eDs
bff N22
'max s
sDs
For R = -1 loading only,
leads to a formulation in terms of
the standard strain-life curve
![Page 18: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/18.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 17 of 45
Cast Iron Analysis – Strain Life
Elastic-plastic behavior in stress concentrations control fatigue
life
Rainflow counting is used to determine damaging events
corresponding to closed elastic-plastic hysteresis loops.
Mean stresses are tracked according to input loading
sequences
Smith-Watson-Topper parameter accounts for mean stress
Neuber' Rule is used to determine notch root stress and
strains
A new model for stress-strain response is needed
![Page 19: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/19.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 18 of 45
Gray Iron Hysteresis Loop
![Page 20: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/20.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 19 of 45
Monotonic Behavior – Nodular Iron
![Page 21: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/21.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 20 of 45
Monotonic Behavior – Gray Iron
Much stiffer in compression
No linear region
![Page 22: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/22.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 21 of 45
Important Observations (Gilbert)
1. Curvature in the tensile stress/strain curve is not
only associated with elastic and plastic deformation
of the matrix, but is also due to volume increase in
the spaces occupied by the graphite.
2. This volume increase is most pronounced on the
specimen surface where graphite flakes, oriented
perpendicularly to the load can actually crack or
debond from the matrix.
3. Gray iron is stiffer in compression than tension
because the spaces occupied by the graphite do
not see corresponding decreases in volume.
![Page 23: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/23.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 22 of 45
Inspiration
P d
1
2
Displacement, d
Load, P
Elastic
Elastic - Plastic
Fully Plastic
sys
e
![Page 24: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/24.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 23 of 45
Inspiration - Add Broken Bars
![Page 25: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/25.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 24 of 45
Inspiration - Add Broken Bars
![Page 26: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/26.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 25 of 45
Strategy – Divide and Conquer
![Page 27: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/27.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 26 of 45
Problem - Elastic Modulus
![Page 28: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/28.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 27 of 45
Secant Modulus
sS linear 0(E ) E m
e e eS R
e s
s s
S S linear
0
/ (E )
/ (E m )
![Page 29: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/29.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 28 of 45
Remaining Plastic Strain
s e
1 n
RK
s s e
s
1 n
0E m KNew stress-strain equation
![Page 30: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/30.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 29 of 45
Monotonic Behavior – Gray Iron
s se
s
C1 n
0 C CE m K
s se
s
T1 n
0 T TE m K
![Page 31: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/31.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 30 of 45
Composite Rule of Mixtures
s s
s - s
m m g g
m g g g
F A A
1 A A
e - m g g gF E 1 A E AElastic
![Page 32: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/32.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 31 of 45
Bulk Response Like Steel?
Dominated by steel matrix
Symmetric?
Masing Behavior?
Material Memory?
m g gE E , A 0.25
s se
s
1 n
B B
0 B B BE m K
-
s s DsB B Bi i 1
Ds Ds
De Ds
1 n
B B
0 B B B
2E m 2 2K
![Page 33: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/33.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 32 of 45
Symmetric Area
![Page 34: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/34.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 33 of 45
Internal Graphite Behavior
Greater stiffness in compression
Graphite approaches incompressibility
Compressive stress is transferred to to the
inherently stiffer matrix
s s - s e
e
G M BC Cif 0
0 if 0
![Page 35: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/35.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 34 of 45
Surface Behavior
Eu
Debonded graphite in tension
Unloading modulus provides evidence
![Page 36: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/36.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 35 of 45
Surface Behavior Equations
su 0 uE E m
s u u max
eff0 0
E mA 1
E E
s sM T eff B T( ) A ( )
ss
s
0 M TB T
0 u M T
E ( )( )
E m ( )
Easier way to get bulk stress
![Page 37: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/37.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 36 of 45
Stress-Strain Model
s s s - seff B G eff ccA ( ) (1 A )
![Page 38: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/38.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 37 of 45
Crack Closure Stress
s e - e qcc maxQ( )
- e - e2 1 maxq (B / B )( )
![Page 39: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/39.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 38 of 45
Mean Stress
-s e 0.25max a f1.82(N )
![Page 40: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/40.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 39 of 45
Life Prediction Procedure
![Page 41: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/41.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 40 of 45
Stress-Strain Results
![Page 42: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/42.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 41 of 45
Stress-Strain Results
![Page 43: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/43.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 42 of 45
Stress-Strain Results
![Page 44: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/44.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 43 of 45
Stress-Strain Results
![Page 45: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/45.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 44 of 45
Model User’s
John Deere
Caterpillar
eFatigue.com
Safe Technology
nCode International
![Page 46: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/46.jpg)
Fatigue Seminar © 2003-2012 Stephen Downing, University of Illinois at Urbana-Champaign, All Rights Reserved 45 of 45
eFatigue
![Page 47: ME 231 · 02/07/2014 · Title: ME 231 Author: Darrell Socie Created Date: 4/18/2012 3:44:09 PM](https://reader033.vdocuments.us/reader033/viewer/2022060908/60a347fa830e025c403b9fc6/html5/thumbnails/47.jpg)
Cast Iron Fatigue