Instruction: 
					Hardness tester is used to determine the
					hardness of materials, and hardness test is a
					means to judge the quality of metal
					materials or parts of products. The so-called
					hardness is the ability of a material to
					resistthe indentation of another body
					without residual deformation under certain
					conditions. The greater the resistance, the
					higher the hardness, and vice versa.