Crystallography Flashcards
(28 cards)
Name the 4 types of crystal structure
- Simple Cubic Structure (cP)
- Body Centred Cubic Structure (BCC)
- Face Centred Cubic Structure (FCC)
- Hexagonal Close Packed Crystal Structure (HCP)
Symmetry in a cP structure
- ax = ay = az
- alpha = beta = gamma = 90deg
Percent Packing Efficiency in cP structure
52%
Coordination number of cP structure
6
Symmetry in a BCC structure
- ax = ay = az
- aplha = beta = gamma = 90deg
Coordination Number in a BCC structure
8
Percent Packing Efficiency in a BCC structure?
68%
Examples of cP structure
NaCl - Table Salt
Examples of metals with BCC structure
Iron, Chromium, Tungsten, Vanadium
What can FCC also be known as?
Cubic Closest Packed (CCP)
Symmetry in an FCC structure
- ax = ay = az
- alpha = beta = gamma = 90deg
Coordination number in an FCC structure
12
Percent Packing Efficiency in an FCC structure
74%
Examples of metals with FCC structure
Aluminium, Copper, Nickel, Cobalt
Order in Z direction for cP
AAAAAA
Order in Z direction for BCC
ABABAB
Order in Z direction for FCC
ABCABC
Symmetry in an HCP structure
- alpha = 120deg
- beta = gamma = 90deg
- ax = ay
Defects in Crystals
- Vacancies
- Dislocations
What kind of defect is a Vacancy?
Point Defect
What kind of defect is a Vacancy?
Point Defect
What kind of defect is a dislocation?
Linear Defect
What increases with quantity of dislocations?
Strength
5 types of imperfections in metal crystal structures
- Vacancy
- Self Interstitial Atom
- Interstitial Atom
- Substitutional atom (rsubrmatrix)
