Hardness Test of Heat Treatment Workpieces

Metal heat treatment processes include annealing, normalizing, quenching, tempering, solution treatment, aging, etc. It is very important to test the hardness of workpieces (materials) under various heat treatment process conditions.

The following introduces the hardness test methods of various metal materials under various heat treatment process conditions.

1. Annealing

Annealing heat treatment is divided into complete annealing, incomplete annealing and stress relief annealing. The purpose of annealing is to refine the structure, reduce hardness, improve cutting performance and remove internal stress.

The mechanical properties of annealed materials can be tested by tensile tests or hardness tests. Many steels are supplied in the annealed heat treatment state. The hardness test of steel can be tested by Rockwell hardness tester to test HRB hardness. For thinner steel plates, steel strips and thin-walled steel pipes, surface Rockwell hardness tester can be used to test HRT hardness.

2. Normalizing

The purpose of normalizing heat treatment is to eliminate stress, refine the structure, improve cutting performance, and pre-treat for quenching annealing.

The hardness test of normalizing heat-treated workpieces can also be carried out using a Rockwell hardness tester to test the HRB hardness.

3. Quenching and tempering

Many steel parts must undergo quenching and tempering heat treatment to obtain the required hardness.