AIT Material Science 2

Question 1

Which heat treatment process involves heating steel above its critical temperature and then cooling it slowly in the furnace to reduce hardness?

Accepted Answer

Annealing

Answer

Annealing involves heating steel above its critical temperature and slow furnace cooling to relieve stresses and reduce hardness.

Question 2

What property describes a material's ability to return to its original shape after the applied stress is removed?

Accepted Answer

Elasticity

Answer

Elasticity is the ability of a material to recover its original shape and size when the deforming force is removed.

Question 3

Which type of cast iron contains graphite in a flake form, making it brittle but with excellent compressive strength?

Accepted Answer

Gray cast iron

Answer

Gray cast iron contains graphite in flake form, which gives it high compressive strength but low tensile strength and brittleness.

Question 4

What is the purpose of the carbon content in steel alloys for trade applications?

Accepted Answer

To control hardness and strength

Answer

Carbon content in steel primarily controls its hardness, strength, and hardenability through heat treatment processes.

Question 5

Which bonding type is responsible for the high melting points and hardness of ceramic materials?

Accepted Answer

Ionic and covalent bonding

Answer

Ceramics have high melting points and hardness because of strong ionic and covalent bonds between their atoms.

(AIT) Apprenticeship and Industry Training Practice Test