Mechanical performance testing methods are mainly divided into two categories, one is stretching test, and the other is hardness test.
1. The stretch test is to control the spiral steel into a sample. Pull the sample to the break on the stretch test machine, and then determine one or several mechanical properties. Usually, only the tensile strength, the yield strength, and the elongation rate of the extension after disconnection are measured. And section contraction rate. The stretch test is a metal material, which is a more basic mechanical performance test method. Almost all metal materials have stipulated stretch tests as long as they have requirements for mechanical properties. Especially those materials that are not easy to conduct hardness tests, stretch tests have become the only mechanical performance testing means.
2. The hardness test is to slowly press a hard pressure head into the surface of the sample according to the prescribed conditions, and then test the indentation depth or size to determine the size of the material hardness. Hardness test is a simple, faster, and easier implementation method in material mechanical performance tests. The hardness test is non -destructive, and there is a similar conversion relationship between the hardness value of the material and the tensile strength. The hardness of the material can be converted into the tensile strength value, which is of great practical significance. At present, this method is more commonly used.
Comparison of the two. The stretch test is not convenient to test, and it is very convenient to convert from hardness to the intensity. Therefore, people are more and less testing the hardness of the materials and less testing their strength. Especially due to the continuous progress and innovation of hardness meter manufacturing technology, some materials that could not directly test hardness, such as spiral steel pipes, stainless steel plates, and stainless steel belts, are now possible to directly test hardness. Therefore, a hardness test gradually replaces the trend of stretching test.
