Method for hardness test of cold drawn tube

- Apr 09, 2020-

Many customers purchase cold-drawn tube materials to make products, which have requirements on its hardness. For example, can the hardness of a cold-drawn steel welded tube of a certain specification meet the requirements?

Hardness is a performance index to measure the softness and hardness of the material. There are many methods of hardness testing, the principles are different, and the measured hardness values and meanings are also different. Commonly used is the static load indentation hardness test, that is, Brinell hardness HB, Rockwell hardness HRA, HRB, HRC, Vickers hardness H, and other hardness values indicate the ability of the material surface to resist intrusion of hard objects. The Leeb hardness Hl and Shore hardness HS belong to the rebound test hardness test, and its value represents the magnitude of metal elastic deformation work. Therefore, hardness is not a pure physical quantity, but a comprehensive performance index reflecting the elasticity, plasticity, strength and toughness of materials. A

Machine factories commonly use this cold-drawn tube Rockwell hardness. It is the hardness test of heat-treated parts. Rockwell hardness test is generally carried out. The cold-drawn steel Rockwell hardness test method is used because the method is simple. Regardless of whether it is Brinell hardness or Vickers hardness, the test method needs to measure the diameter and diagonal length of the pit pressed by the indenter, which is very troublesome. The Rockwell hardness test method is the same as pressing the indents with the indenter, but the hardness value can be determined only by the depth of the indents. Therefore, the testing machine can directly display the size of the pit, without the need to measure, as long as the test action of the indenter pressure, the hardness value can be obtained. A