CHAPTER 4

Question 1

advantages of aluminum

Answer 1

• most plentiful metal on Earth
• 1/3 the density of steel
• high strength to weight ratio
• good thermal and electrical conductivity
• anodizing or hard coating for protection
• weldable alloys
• easy to recycle
• corrodes slightly but does not rust
• high reflectivity
• can be die cast
• easily machined
• nonmagnetic
• nontoxic

Question 2

uses for aluminum

Answer 2

1. primarily for containes, packaging, aircrafts and automobiles
2. civil projects : architectural and finishing elements (doors, windows) + small amount used for electrical wiring
3. not used extensively for structural members. expensive, coefficient of thermal expansion quite high

Question 3

wrought definition

Answer 3

worked by being forged or hammered

Question 4

cast definition

Answer 4

poured into a mold to give it its shape

Question 5

graphic : x = temperature, y = tensile strength of aluminum. behaviour?

Answer 5

from stronger at -200 °C and reduces slowly with increasing temperature