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Review: FE Exam
• Text: “Materials Science and Engineering:
An Introduction,” 6th ed., William D.
Callister, Jr., Wiley, 2003.

Review: FE Exam
– Part 1 – atomic structure & bonding
• What holds materials together?
– Part 2 – Imperfections in solids
• How are they packed?
– Part 3 – mechanical properties
• How do they deform?

Review: Chapter 1 – Introduction
• Types of Materials
– Metals
– Polymers
– Ceramics

Review: Chapt 2-Atomic Structure
• Atomic Number, Atomic Weight, etc.
• Periodic table
– Electron Structure - valence electrons –
unfilled shells
• Bonding
– ionic
– covalent
– metallic
– van der Waals

Review: Chapt 3 – Crystal
Structures
• Unit Cell
– Metals
• BCC
• FCC
• HCP
• Atomic packing factor
• Coordination number
• Crystallographic directions [uvw]
families of directions <uvw>
• Linear density of atoms (ld) = atoms/unit
length

Review: Chapt 3 – Crystal
Structures (cont.)
• Miller indices of planes (hkl)
families of planes {hkl}
• Planar density (pd) = # of atoms/ unit area
(pd) = S.A. atoms/S.A. unit cell
• X-Ray Diffraction
– Bragg’s law



sin
2
n
dhk

Review: Chapter 4
• Imperfections
– Point defects
• Interstitial
• Vacancy
• Substitution
• Solid solutions
– Line defects
• Edge dislocation - Burgers vector perpendicular to
dislocation line
• Screw dislocation - Burgers vector parallel to
dislocation line
– Planar defects
• Twin
• Stacking fault
• Grain Boundary

Review: Chapter 4 (cont.)
• Microscopy
– Optical
– Electron Microscopy
– Sample Prep – polishing & etching

Review: Chapter 5
• Diffusion
– Vacancy diffusion
– Interstitial diffusion
– Fick’s First Law
Second Law
– Temp effect
– Slab- non-steady state
dx
dC
D
J 

2
2
x
C
D
t
C













RT
Q
exp
D
D d
0










Dt
2
x
erf
1
C
C
C
C
0
s
0
x

Review: Chapter 19
• Thermal Properties
– Heat Capacity
• C = dQ/dT Cp > Cv
– phonons
– thermal expansion coefficient
• l/l = l T
– thermal conduction of heat
• q = -k (dT/dx)
– k = heat transfer coefficient

Review: Chapter 6
Mechanical Properties
• Stress vs. strain
• Hooke’s law s  E e
A
F
0

s
0
0


 

e
sy
TS
sF
E

Review: Chapter 6
• Poisson’s Ratio
• Toughness
• Resilience
• Hardness
z
x
z
y
e
e


e
e




Review – Chapter 7
Dislocations and Strengthening Mechanisms
• Deformation by motion of dislocations
– Slip plane – plane of easiest deformation
– Slip direction – direction of easiest slippage
– Slip system – direction and plane
• Applied stress must be resolved along slip direction
–  = s cos cos
• Twinning
• Mechanism of strengthening
– Grain size reduction
– Solid-solution hardening
• impurities reduce mobility of dislocations
– Strain hardening %CW = 100 x (A0-Af)/A0
• Recovery, recrystallization, & grain growth

Fracture – failure
– Ductile fracture
• Large deformations
– cone & cup
– small necked regions
– Brittle fracture
• Almost no deformation other than failure
– transgranular – within grain
– intergranular- between grains

Review, Chapter 8 (cont.)
• Griffith Crack - Stress concentration
– Critical stress
• Fatigue – cyclic stress
• Creep
2
1
s
c
a
E
2









s
0
t
m K s

s

Review- Chapter 9
Phase Diagrams
• Isomorphous system
– 1. How many &
which phases
– 2. Use tie line to
read compositions
– 3. Use lever rule
to get weight
fractions

Review- Chapter 9
• binary eutectic system
– 1. How many & which phases
– 2. Use tie line to read compositions
– 3. Use lever rule to get weight fractions

Review- Chapter 9 (cont.)
• Eutectic L S1+S2
• Eutectoid S1 S2+S3
• Peritectic S1+L S2
• Hypoeutectoid
• Hypereutectoid
cool
heat
cool
heat
cool
heat

Review - Chapter 10
Rate of Phase Transformation
• Nucleation process

Review - Chapter 10 (cont)
• Phase transformations vs. temperature
and time
– Pearlite
– Martensite
– Bainite
– Spheroidite
Chapter 11
• Heat Treatments

Fabrication of Metals
• Forming
– Forging
– Rolling
– Extrusion
– Drawing
• Casting
• Powder metallurgy
• Welding
• Machining
• Alloy Nomenclature
• Cast Irons – addition of Si catalyzes graphite
formation
• Refractories

Ceramics
• Crystal structures
– oxygen larger – generally in FCC lattice
– cations go in lattice sites based on
• size
• stoichiometry
• charge balance
• bond hybridization
– no good slip planes – brittle failure
• Silicates
– built up of SiO4
4-
– layered
– countercations to neutralize charge

Chapter 12 – Ceramics
• Carbon forms
– diamond
– graphite
– fullerenes
– amorphous
• Lattice imperfections
– Frenkel defect – cation displaced into
interstitial site
– Schottky defect – missing cation/anion pair
• Phase diagrams
• Mechanical properties

Chapter 13 – Ceramics (cont)
• Glasses
– amorphous sodium or borosilicates
– Forming
• pressing
• drawing
• blowing
• Clay products - forming
– Hydroplastic forming
– Slip casting
– Refractories
– Powder pressing
• Cements
• Advanced ceramics

Chapter 14 – Polymers
• Types of polymers
– Commodity plastics
• PE = Polyethylene
• PS = Polystyrene
• PP = Polypropylene
• PVC = Poly(vinyl chloride)
• PET = Poly(ethylene terephthalate)
– Specialty or Engineering Plastics
• Teflon (PTFE) = Poly(tetrafluoroethylene)
• PC = Polycarbonate (Lexan)
• Polysulfones
• Polyesters and Polyamides (Nylon)

Chapter 14 – Polymers
• Molecular Weight
– Actually a molecular weight distribution
– Mn = Number-averaged molecular weight
– Mw = Weight-averaged molecular weight
– Polydispersity = Mw/Mn
• A measure of the width of the distribution
• Chain Shapes
– linear
– branched
– crosslinked
– network

Chapter 14 & 15 – Polymers
• Isomerism
– Isotactic
– Syndiotactic
– Atactic
– Cis vs. Trans
– Copolymers
• Random
• Alternating
• Block
• Crystallinity
– Spherulites

Chapter 16 – Composites
• Combine materials with objective of getting a
more desirable combination of properties
• Dispersed phase
• Matrix
• Particle reinforced
– large particle
– dispersion strengthened
• Rule of mixtures
– Upper limit Ec(u) = EmVm + EpVp
– Lower limit  
E
V
E
V
E
E
E
m
p
p
m
p
m
c




Chapter 16 – Composites
• Reinforced concrete
• Prestressed concrete
• Fiber reinforced
– Short vs. long fibers
– Critical length
– allignment
c
f
c
2
d

s



Chapter 18 – Electrical Properties
Definitions
• R = resistance = Ohms
•  = RA/l = resistivity = ohm meter
• s = 1/ = conductivity
• C = Q/V = capacitance
• er = e/eo = dielectric constant

Chapter 18 – Electrical Properties
• Energy Bands – valance vs. conduction
– Conductor – no band gap
– Insulator – wide gap
– Semiconductor – narrow gap
• Intrinsic – pure or compound
– Electron vs. hole (which carries charge)
• Extrinsic (doped)
– n-type – donor levels – extra electrons
– p-type – acceptor levels – extra holes
• Microelectronics
– pn junction – rectifier diode
– npn transistor

Chapter 20 – Superconductivity
• Tc = temperature below which
superconducting
= critical temperature
Jc = critical current density if J > Jc not
superconducting
Hc = critical magnetic field if H > Hc not
superconducting
• Meissner Effect - Superconductors expel
magnetic fields

Chapter 21 – Optical Properties
• Electromagnetic radiation
• Angle of refraction at interface





hc
h
E
)
medium
in
light
of
velocity
(
v
)
vacuum
in
light
of
velocity
(
c
index
refractive
n 




 sin
sin
n
n

Chapter 21 – Optical Properties
• Light interaction with solids
– Reflection
– Absorption
– Scattering
– Transmission
• Semiconductors – absorb light with energy
greater than band gap
• Luminescence – emission of light by a material
– phosphorescence = If very stable (long-lived = >10-8 s)
– fluorescence = If less stable (<10-8 s)
• LASERS – coherent light
• Fiber optics
ty
reflectivi
2
n
1
n
R
2










t
I
I
ln
0










Questions???
• Contact Prof. David Rethwisch to discuss
questions.
– office 4139 SC
– Phone 335-1413
– email david-rethwisch@uiowa.edu

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