MEM 333 Mechanical Behavior of Materials, Winter 2014
MEM 333001
Mechanical Behavior of Materials
Winter, 2014
Mr. UKei Cheang
Dr Alan Lau
Name and
email
[email protected][email protected]
(Teaching Assistant)
(Instructor)
Office Hours
Monday, Tuesday and F
1 1.1
For given da/dN versus AK graph in Fig. 11.3, for the straight line
portion, obtain constants for da/dN = C (AK )m .
The data in the central portion of the graph form an approximate
straight line on the loglog plot, so that a t to Eq. 11.10 is re
9.5
For given stresslife data on Ti6A14V: (3) Plot on loglog coordinates
and nd approximate constants A , B . (b) Find improved values A , B by
least squares; calculate o'f , b .
ca = ANf, 0a =0f(2Nf)b
Data
ca, MPa Nf, cycles x = log ca , y = log Nf
10
9.21
For SAE 1015 steel (normalized), with 0'0 = 160 MPa, estimate the
life for Gm of (a) zero, (b) 70 MPa tension, and (c) 70 MPa
compression. Use the Morrow equation.
1/5
1 0'
aa=<oyomx2Nf)b, Nf=2[~ J
0" f 6m
MLL
M
Stresses in MPa ' Morrow
Ga cm Nf, cy
I 03
EMF. K31 (T0 at
0C MPOLW MPCX rm mm.
(0 #50 42 700 0.00HS Us
<2>
_ The steel is much Wort:
foleramT 0f Ial~os ai Hm
hi9 her hsrmperafure (2). 4 8'4 .Ca/CM/afe 0% for var/oars 9/1/4244
Wafer/225 4440 CWWea/rz 024 +remas.
a =_1_ KIC)2:_1_(56'MPQW)
11.17
For the three given data points on 174 PH stainless steel, obtain
approximate C 0, m , and y for the Walker equation.
Point da/dN AK R m = 2.458
mm/cycle MPa J; 0004 = 2.631 E08
1 3.68E~03 124. 0.04 00.3 = 6.585E08
9.98E06 1 1 .2 0.04 mmmyde
3
' 11.43
A centercracked plate of AISI 4340 steel has given dimensions and
initial crack length, and it is cycled between given minimum and
maximum loads. (a) Estimate the crack length at failure. (b) Calculate
the life om numerical integration.
Record
Problem Statement
Given the following material properties:
and a known equation for crack growth rate in the given material:
Find how many cycles the machine part will last for the following loading cycle:
1 cycle of and
1 cycle of and
where each cycle al
MEM 333 — Summer 2015, Aug 19
Mechanical Behavior of Materials
Makeup Exam
Problem #1
As an engineer at a bio—medical corporation, you are investigating the fatigue behavior of 3—D
printed prosthetic legs. Due to manufacturing, the leg can have embedded
MEM 333 Summer 2015, Midterm Exam 1
MEM 333  Summer 2015, July 15, 2014
Mechanical Behavior of Materials
Midterm 1
Problem #1.
As part of a design team for building a new robotic surgical system, you are investigating new materials
for one of the robot
MEM 333 Summer 2015 Midterm #2
MEM 333  Summer 2015, Aug 12, 2015
Mechanical Behavior of Materials
Midterm 2
Problem #1. Working at BMW, you have been asked to reverseengineer the chassis of a rival
car that is known to have good fatigue life. To help
MEM 333 Mechanical Behavior of Materials, Summer 2015
MEM 333
Mechanical Behavior of Materials
Summer, 2015
Name and
email
Office Hours
Location
Dr Simon Chung
[email protected]
(Instructor)
Young Bok(Abraham) Kang
[email protected]
(Teaching Assistant)
Afte
z._1_
For the given state of stress applied to Si3N4, determine the
safety factor against fracture. First calculate principal normal
stresses. Then use the maximum normal stress fracture
criterion to obtain the effective stress and safety factor.
Stress
g1
A state of stress on the free surface of a solid body is given by ox, Gy,
and 17,6, as below. (a) Evaluate the two principal normal stresses and the
one principal shear stress that can be found by coordinate system
rotations in the xy plane, and give t
Lessons Learned
After the dust had settled, and various scientific and government investigations
into the cause of the disaster had been conducted, the public was still left with the
question on how to move on. How could we improve our infrastructure on t
MEM 333: Mechanical Behaviour of Materials
Group Project: Case Study
I35W Mississippi River Bridge Collapse
Winter 20132014
Team ?
Submitted to:
Dr. Alan Lau
Drexel University Mechanical Engineering Department

Introduction
The i35W Mississippi River
Spokes
Spencer Honadel
Background
Spokes have been part of wheels since time immemorial. They are a cheap and effective way
of reducing weight while maintaining strength. Bicycles especially are built with weight in mind,
and keeping a good strengthtowe