EGR 221- Materials Science
Final Exam Review Sheet, 2008
Final exam will be CLOSED BOOK, CLOSED NOTES, NO CALCULATOR.
Determine planes and directions in cubic systems given the Miller indices, and visa versa
Be able to explain how and why the following can affect strength: impurities (solid
solutions), precipitates, grain boundary/grain size
Be able to explain what causes dislocations to move, what inhibits them from moving,
and what direction they move in a crystal (slip systems).
Be able to describe (in words) the following mechanical properties and be able to
determine them from a stress-strain curve: yield strength, tensile strength, toughness,
ductility, Young’s modulus.
Be able to describe (in words) the following mechanical properties and briefly describe
testing used to determine them: hardness, Poisson’s ratio.
Be able to read phase diagrams and determine compositions of phases and determine how
much of each phase is present given overall composition and temperature – and visa
versa. This includes determining amounts of pearlite and proeutectoid ferrite or
cementite that may be present based on overall composition of plain carbon steel.
Be able to describe the following microstructures in steel (how are they created, what are
their morphologies, relative hardness/strength, toughness/ductility): austenite,
pearlite, bainite, martensite, spheroidite, tempered martensite. Need be able to use a
Time-Temperature-Transformation diagram (TTT diagram, a.k.a. isothermal
diagram) to determine which of the above microstructures would be formed based off
a given cooling history.
Be able to describe the difference between hardening mechanisms of steel (such as
formation of martensite) and precipitation heat treating of aluminum alloys.
Understand the microstructural differences between thermosetting and thermoplastic
polymers (linear/branched vs. crosslinked/networked). Understand the general effect
that temperature and strain rate have on strength, ductility and stiffness.
Understand the following types of corrosion well enough to explain how they are
damaging and how they may be prevented: uniform attack, galvanic corrosion,
crevice corrosion, pitting.
Additional Terminology:
crystal
substitutional solid solution
interstitial solid solution
non-steady state diffusion (transient)
steady state diffusion
phase
