Vickers hardness, represented by the symbol HV, was proposed by Robert L. Smith and George E. Sandland in 1921 at Vickers Ltd. It uses a diamond regular pyramid indenter with a relative angle of 136 degrees between its faces, which is pressed into the surface of the test sample under a specified loa

Hardness of metal materialsHardness is one of the important indicators for measuring the mechanical properties of metal materials, which measures their ability to resist external forces such as indentation or scratching. Hardness testing is the fastest, most economical, and simplest test method for

Tapping is the process of using a tap to cut internal threads into the hole of a workpiece.picture(1) The factors that determine the performance of the tap include:Workpiece materialcutting speed Cutting edge materialhiltTap formThe size of the holeThreaded knife handlecutting fluidKong Shen(2) Pitc

Quenching and tempering treatment usually refers to the quenching of steel and subsequent high-temperature tempering, which is a common process in steel heat treatment. The purpose is to improve the mechanical properties of metals through appropriate heat treatment processes, so that they have good