Flashcards
Material Science Exam 4 Flashcards
Cards in this deck (35)
- 1Metal Alloy ClassificationsFerrous and Nonferrous
- 2Classifications of Ferrous AlloysSteels and Cast Irons
- 3Classifications of SteelsLow Alloy and High Alloy
- 4Low Alloy Carbon wt%Low carbon - <0.25 wt%
Med carbon - 0.25-0.6 wt%
High carbon - 0.6-1.4 wt% - 5Examples of low carbon alloysPlain and HSLA (high strength low alloy)
Automobiles, bridges - 6Examples of medium carbon alloysPlain and heat treatable
Gears, hammers - 7Examples of high carbon alloysPlain and tool
Wear application, drills - 8Examples of high alloysTool and stainless
Saws, appliances - 9How to name steelsPlain Carbon Steels - 10xx
Plain Carbon Steels (resurfurized) - 11xx
Mn - 15xx
Mo - 40xx
Ni, Cr, Mo - 43xx
Mo (0.5%) - 44xx
xx = wt% C
Cr (>11%) - Stainless Steel - 10Cast IronsFerrous
>2.1 wt% C (mostly 3-4.5%)
Low melting
Brittle
Slow process - 11What are nonferrous alloys made of?Cu, Al, Ti, Mg, Noble Metals, Refractory Metals
- 12Types of metal facbricationHot working, cold working, casting
- 13Differences between hot working and cold workingDeformation temperature
Hot working - large deformations
Cold working - strain hardening, small deformations - 14CastingMold is filled with molten metal
Common, not the best method - 15Bond HybridizationHybrid electron orbitals form
Possible when there is significant covalent bonding - 16Factors of ceramic crystal structuresMagnitude of ion electrical charge - should be neutral
Relative sizes of cations and anions - should be stable - 17Oxide structuresOxygen anions larger than metal cations
Close packed oxygen in lattice
Usually FCC
Cations fit into interstitial sites among oxygen ions - 18Coordination numberIncreases as radii of cation to anion increases
4, 6, 8 (tetrahedral, octahedral, and cubic) are most common for ceramics - 19Coordination number matched up to crystal structure4 - ZnS
6 - NaCl
8 - CsCl - 20Ratios matched up to coordination numbers2 - <0.155
3 - 0.155-0.225
4 - 0.225-0.414
6 - 0.414-0.732
8 - 0.732-1.0 - 21Density formuladensity=(n'(sumAc+sumAa))/(VcNa)
- 22Point defects in ceramicsVacancies - cations and anions
Interstitials - cations only - 23PolymerMany repeating units
Macromolecules - 24Composition of polymersMade up of H and C
Each carbon is singly bonded to 4 other atoms - 25How do polymers formAddition (chain) of condensation (step)
- 26Addition polymerizationInitiation, propagation, and termination
- 27Condensation polymerizationTaking out water
- 28Molecular WeightMass of a mole of chains (more chains=higher M)
- 29Molecular Weight DistributionMn=sumxiMi
Mw=sumwiMi - 30Molecular shape of polymersChain bending and twisting is possible
Not necessary to break bonds to alter shape - 31CopolymersTwo or more monomers polymerized together
Random, alternating, block, or graft - 32Crystallinity in PolymersCrystal structure in terms of unit cells
Chain folded structure - 33Stress Strain Behavior in PolymersFracture strength is low
Deformation strains is higher - 34Temperature and Strain Rate effect on PolymersDecreasing temperature and increasing strain rate increases modulus of elasticity and tensile strength but decreases %fraction-%yield stress
- 35Polymer AdditivesFillers improve toughness and decrease cost, plasticizers increases makes polymers less brittle
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- Engineering Flashcards on Material Science Exam 4 Flashcards, created by Anna Grunkemeyer on 05/12/2024.
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- Anna Grunkemeyer
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