Stainless steel tube hardness

Stainless steel pipe is commonly used Brinell, Rockwell, Vickers three hardness indicators to measure its hardness.

Brinell hardness

In the stainless steel pipe standard, Brinell hardness is the most widely used, often with indentation diameter to express the hardness of the material, both intuitive and convenient. However, it is not applicable to steel pipes with harder or thinner steel.

Rockwell hardness

The Rockwell hardness test of stainless steel pipe is the same as the Brinell hardness test, which is the indentation test method. The difference is that it measures the depth of the indentation. Rockwell hardness test is a widely used method at present, and HRC is second only to HB in the steel pipe standard. Rockwell hardness can be applied to the determination of metal materials from very soft to very hard, it makes up for the Brinler method is not, simpler than Brinler method, can directly read out the hardness value from the dial of the hardness machine. However, due to its small indentation, the hardness value is not as accurate as the Brinler method.

Vickers hardness

The Vickers hardness test of stainless steel tubes is also an indentation test method that can be used to determine the hardness of very thin metal materials and surface layers. It has the main advantages of the Brucella and Rockwell methods, and overcomes their basic shortcomings, but it is not as simple as the Rockwell method, and the Vickers method is rarely used in the steel pipe standard.

Hardness testing

The inner diameter of the stainless steel pipe is above 6.0mm, and the wall thickness is below 13mm. The annealed stainless steel pipe can be tested by W-B75 Vickers hardness tester, which is very fast and simple, and is suitable for rapid and non-destructive qualified inspection of stainless steel pipe. Stainless steel tubes with inner diameter greater than 30mm and wall thickness greater than 1.2mm were tested for HRB and HRC hardness using a Rockwell hardness tester. Stainless steel tubes with an inner diameter greater than 30mm and a wall thickness less than 1.2mm were tested for HRT or HRN hardness using a surface Rockwell hardness tester. Inner diameter less than 0mm, more than 4.8mm stainless steel pipe, using the pipe special Rockwell hardness tester, test HR15T hardness. When the inner diameter of the stainless steel pipe is greater than 26mm, the hardness of the inner wall of the pipe can also be tested with a Rockwell or surface Rockwell hardness tester.