Introduction to the hardness testing method of stamping materials

The main purpose of the hardness test of stamping parts is to determine whether the annealing degree of the purchased metal sheets is suitable for the subsequent stamping parts processing. Different types of stamping parts processing techniques require plates of different hardness levels.　　Hot-rolled steel sheets are usually thicker, and the Brinell hardness tester is generally specified in the steel standard to test the hardness. It is also feasible to use Rockwell hardness tester to detect hot-rolled steel plates, and HRB scale (the choice of Rockwell hardness tester scale) can be used. The portable Rockwell hardness tester is used to test hot-rolled steel plates, which can be tested without sampling, and the operation is very simple.　　A variety of cold-rolled steel plates used for stamping parts processing mainly use Rockwell hardness tester to test the hardness, usually HRB scale, harder HRC scale. Thin plate material can use Webster hardness tester, surface Rockwell hardness tester HRN or HRT scale can also be used.　　The hardness of the brass plate used for stamping parts can be tested with the HRB scale of the Rockwell hardness tester. The softer brass plates and red copper plates use HRF scales. Thinner plates use HRT scales.　　Aluminum alloy plates used for stamping parts can be tested with a Webster hardness tester. When the thickness of the material is greater than 13mm, a Barcol hardness tester can be used. Pure aluminum plates or low-hardness aluminum alloy plates should use a Barcol hardness tester.　　Various thin plates of various metals used for stamping parts processing can use the HR30T scale of the surface Rockwell hardness tester and cooperate with the diamond anvil to test the HR30Tm hardness value in this way. The thickness of the tested sheet can be less than 0.05mm. This test method is specified in Appendix A of the national standard GB/T230.1-2004. The HR15T and HR45T scales of the surface Rockwell hardness can also be used, and the hardness value is converted into HR30Tm after the test.