Week 5 Flashcards
Define crystal structure
(As a question)
How are the atoms, ions, or molecules arranged?
Define unit cell
The smallest repeating unit that can build a crystal
Define lattice parameter
Define lattice
Define crystal basis
Lattice + Basis = ______ _____
Crystal structure
What are the 4 Bravais lattices we focus on
What does an FCC look like
What does a BCC look like
What does a hexagonal-close packed look like
(And acronym)
HCP
What does simple cubic look like
And acronym
SC
What question does atomic packing factor answer
SC: not normally seen in _____ (polonium = bad idea)
Metals
BCC: give 2 examples
Steels
High temp titanium
FCC: give 2 examples
Aluminum
Copper
HCP: give 3 examples
Zinc
Magnesium
Low temp titanium
BCC: what is the coordination #
(And what does this mean)
CN=8
(8 atoms touching the centre atom)
FCC: what is the coordination #
CN=12
What does finding the LFP looking like in a cell
Red line or green line
HCP: what is the CN
CN=12
Will theoretical density or experimental density be higher for metals
Theoretical
(Better packing)
What does the stacking sequence for HCP look like
ABAB
What does the stacking sequence for FCC look like
BACBAC
What d question do miller indices answer
Where are we
Miller indices: which coordinates do we always use
Point coordinates: what question do they answer
Where are you relative to the unit cell
Point coordinates: values represent a _____ of the lattice parameter
(Use ______ to separate values)
Fraction
(Commas)
Directions: how to calculate?
Head-tail
Directions: use ______ brackets without _____ or ______
Multiply/divide through to get _____
Use _______ instead of negative sign
Square, commas, spaces
Integers
Bars
5 steps for finding planes
Planes: when do you use round brackets and when do you use curly
Directions: when do you use square brackets and when do you use angle brackets
What type of toughness does Charpy testing measure
Impact toughness
How does charpy testing work
Striking a notched sample with a pendulum hammer (set at an impact energy) and measuring the energy absorbed before the material’s fracture
