Heat Treatments

Question 1

What is the purpose of heat treatments?

Answer 1

To heat and cool metal to alter their properties, including:
- Strength
- Malleability
- Hardness
- Ductility

Question 2

Describe the annealing process and what properties it improves

Answer 2

Metal is heated to a specified temperature, and after a certain period, it’s slowly cooled.

This softens the metal, relieves its internal stresses and improves its ductility and malleability

Question 3

Describe the quenching process and which properties it improves

Answer 3

The metal is heated to a high temperature and rapidly cooled in a quenching medium (water, oil, air)

This increases the metal’s hardness

Question 4

Describe the tempering process and its effect

Answer 4

This follows the quenching process - metal is reheated at a lower temperature and cooled

This reduces the metal’s brittleness

Question 5

Describe the hardening process and its effect

Answer 5

The metal undergoes a austenitizing process, then quenched to form a hard martensitic structure

This increases the metal’s hardness and strength