ME 4010-003 Fall 2015
Group Homework Assignment 7: Fatigue Curves
Assigned Nov. 6, 2015
Due Nov. 13, 2015
1. Consider AISI 1020 CD steel. For bending, estimate the endurance limit Se and the
short-life fatigue strength S1000 if the steel has a machine fin
1. Revisit the deflection analysis in the shaft example problem from the lecture notes, pp. 35-39.
Only deflections are calculated. However, if bearings must be selected for the shaft, you will
want to know what the slopes (rotations) are at the bearing l
Assignment 8 Problem 2 Fatigue Failure
Bottom Part S Hook Analysis
d1
Sy 40000
d2
A = 0.7854
4
F 200
R 0.5
ro 4.5
ri 3.5 rc ri R = ?
R2
= 2.97902
rn
2
2 rc
rc 2 R 2
e rc rn = 0.02098
ci ri rn = 0.52098
co ro rn = 1.52098
M ci
F
+ = 5674.75434
i
A e ri
Assignment 8 Problem 2 Fatigue Failure
Bottom Part S Hook Analysis
d1
Sy 40000
d2
A = 0.7854
4
F 200
R 0.5
ro 4.5
ri 3.5 rc ri R = 3
R2
= 2.97902
rn
2
2 rc
rc 2 R 2
e rc rn = 0.02098
ci ri rn = 0.52098
co ro rn = 1.52098
M ci
F
+ = 5674.75434
i
A e ri