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ALL RIGHTS RESERVED.
SMT 200 Final Topics Study Guide.
Materials with crystalline structure - Answers✔metals, most ceramics, some polymers
materials with amorphous structure - Answers✔glass, polymers
why can some materials pack crystalline - Answers✔uniformity of elements (same size building
blocks)
most efficient packing arrangements - Answers✔FCC and hexagonal close packing
why are glass and polymers amorphous - Answers✔highly viscous silica oxide cools rapidly and
forms random structure
long strands of polymers clump together into a thermoplastic
structure of elastomers and thermosets - Answers✔covalent bonds replace H-bonding to form
cross-links; more cross-links = more rigidity
2 general classifications of metal alloys - Answers✔ferrous and non ferrous
low alloy ferrous - Answers✔not much carbon + other elements
carbon levels for cast iron and steel - Answers✔steel < 2%
cast iron 2 - 6.7%
relationship between carbon content of steel and physical prop. - Answers✔more carbon = more
expensive = more strength = less ductility
3 types of SS - Answers✔austenitic
ferritic
martensitic
iron in the earth - Answers✔makes up about 5% of the crust, exists in ore form with lots of other
compounds
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ALL RIGHTS RESERVED.
SMT 200 Final Topics Study Guide.
Materials with crystalline structure - Answers✔metals, most ceramics, some polymers
materials with amorphous structure - Answers✔glass, polymers
why can some materials pack crystalline - Answers✔uniformity of elements (same size building
blocks)
most efficient packing arrangements - Answers✔FCC and hexagonal close packing
why are glass and polymers amorphous - Answers✔highly viscous silica oxide cools rapidly and
forms random structure
long strands of polymers clump together into a thermoplastic
structure of elastomers and thermosets - Answers✔covalent bonds replace H-bonding to form
cross-links; more cross-links = more rigidity
2 general classifications of metal alloys - Answers✔ferrous and non ferrous
low alloy ferrous - Answers✔not much carbon + other elements
carbon levels for cast iron and steel - Answers✔steel < 2%
cast iron 2 - 6.7%
relationship between carbon content of steel and physical prop. - Answers✔more carbon = more
expensive = more strength = less ductility
3 types of SS - Answers✔austenitic
ferritic
martensitic
iron in the earth - Answers✔makes up about 5% of the crust, exists in ore form with lots of other
compounds
1
