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1: What is the critical point?

A: The temperature of the metal when the structure changes.

2: What is quenching?

A: The steel is heated to the appropriate temperature above the critical temperature, and is cooled quickly after insulation to obtain martensitic structure.

3: What is annealing?

Answer; The steel is heated to a certain temperature, held for a certain amount of time and then slowly cooled to room temperature.

4: What is hardenability?

A: The ability of steel to quench the layer at a certain temperature after quenching under certain conditions.

5: What is tempering?

A: A method of heating steel to a certain temperature below Ac1 to hold it for a certain period of time until it is cooled to room temperature after the tissue transformation is completed.

6: What is tempering?

A: It is a heat treatment method that combines quenching and high temperature tempering.

7: What is the purpose of carburizing?

A: Activated carbon atoms penetrate the surface of the steel to improve the surface carbon content of the steel.

8: What is hot hardening?

A: The ability of steel to maintain hardness at high temperatures.

9: What are the categories of aluminum alloy?

A: Can be divided into deformation aluminum alloy and cast aluminum alloy.

10: What are the categories of copper alloys?

Answer: Can be divided into bronze, copper, brass.