What are the expression methods of steel pipe hardness?
The hardness expression method of seamless steel pipe has Brinell hardness (HB), Rockwell hardness (HRC), Vickers hardness (HV), Leeb hardness (HL) and so on.
Brinell hardness (HB) : with a certain diameter of steel ball or carbide ball, with the specified test force (F) pressed into the surface of the pattern, after the specified holding time to remove the test force, measure the indentation diameter of the specimen surface (L). The Brinell hardness value is the quotient obtained by dividing the test force by the surface area of the indentation sphere.
Rockwell hardness (HRC) : Rockwell hardness test, like Brinell hardness test, is an indentation test method. The difference is that it measures the depth of the indentation. That is, under the action of the first yong test force (Fo) and the total test force (F), the indenter (steel cone or ball) is pressed into the surface of the sample, after the specified holding time, the main test force is removed, and the hardness value is calculated with the measured residual indentation depth increment (e). Its value is an anonymous number, expressed by the symbol HR, and the ruler used is A, B, C, D, E, F, G, H, K and other 9 rulers.
Vickers hardness (HV) : The Vickers hardness test is also an indentation test method, which is to press a positive tetrapyramid diamond indenter with an Angle of 1360 relative to the surface into the test surface with the selected test force (F), and remove the test force after the specified holding time, and measure the diagonal length of the indentation.
