1. Draw the unit cell of FCC structure and show that b = all where b is the distance
between the centers of two adjacent atoms and an is the lattice parameter.
’Pmblem M
cataowe ewe mu; 0% JruJekakearat w) Wu hates m
30C and Fcr. Iron; aaswve Lathe: p
2.1 Rubber specimens, having an initial length of 5 cm, are tested, one in compression
and the other in tension. If the engineering displacements are —1.5 cm and 1.5 cm,
respectively, What will be the ﬁnal lengths of the specimens? What are true
strains,
1. Derive the Griffiths criterion.
2. What is the difference between the fracture feature of brittle materials and ductile
materials?
Ductile failure occurs by (a) the nucleation, growth, and coalescence of voids, (b)
continuous reduction in the metals cr
1
University of California, San Diego
MAE160 Mechanical Behavior of Materials
Second midterm 2016 Winter
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1. What is the theoretical shear strength of the metals. Please
1. Calculate the dislocation spacing in a symmetrical tilt boundary ( =0.5) in
a copper crystal.
2. A polycrystalline sample has 16 grains per square inch in a
photomicrograph taken at magnification 100. What is the ASTM grain size
number?
3. The yield st
3.9 The stress-strain curve of a 70 —30 brass is described by the equation,
0' : 6008 3,35 MPa
until the onset of plastic instability.
(21) Find the 0.2% offset yield stress
(b) Applying Considere’s criterion, ﬁnd the real and engineering stress at the
on
C r y s ta llo g r a p h ic d ir e c tio n s
F o r (1 )
Move so that it starts at a convenient origin The vector is 0i + 1j + 0k c (1)
Direction is the [010] where
A specific direction is given in [ ] A family of directions is given in < > (3) a Cryst
MAE 160 Spring 2010 Assignment 2 Due Tues., April 13 at the beginning of class Read Chapter 2 and work problems: 2.2 (see figure below for problem set-up)
2.11 2.12 2.13 2.20 2.21 2.34 2.42
The problem should read (see posted Errata): A silver monocrystal
U n it c e lls
Chapter 1: Materials: Structure, properties and performance
1
T h e 1 4 B r a v a is la ttic e s
Crystal system orthorhombic
base centered body centered face centered
simple
tetragonal
cubic
Chapter 1: Materials: Structure, properties and p
E n g in e e r in g s tr e s s
Tensile stress, :
Ft
Shear stress, :
Area, A
Fs Fs
Area, A
Ft F = t Ao
original area before loading
Chapter 2: Elasticity and Viscoelasticity
= Fs Ao
1
S h e a r s tr e s s a n d s tr a in
F F F
original rectangular shape
Plastic deformation
p la s tic e la s tic lo a d in g u n lo a d in g
p e rm a n e n t d e fo r m a tio n
e la s tic r e c o v e r y
Chapter 3: Plasticity
1
Plastic deformation (metals)
1. Initial 2. Small load bonds stretch & planes shear elastic + plast
MAE 160
Mechanic al behav ior of materials Spring 2010 T, Th.: 12.30-1:50, CSB 001 F: 12-1:50, CSB 001 Prof essor Joanna Mc Kittrick Dept. MAE EBU II, Rm. 257 Phone Fax 858-534-5425 858-534-5698 jmckittrick @ucsd
Office hours Tues. and Thurs. 3: 30-4:15 a
MAE 160 Spring 2010 Quiz 1 1. What is the difference bet ween HCP and FCC in t erms of stacking of close packed layers A, B, C, etc.? HCP has stacking ABABAB FCC has stacking ABCABCABC 2. Draw the [ 1 10] in a unit cell.
3.
Draw the BCC structure.
Investigation of contribution of {123} slip planes
to development of rolling textures in bcc metals
by use of Taylor models
D.Raabe
In order to describe the evolution of rolling textures in bcc metals, and particularly to assess the contribution of disloc