What is the material used for the grade 8 self tapping screws?
What is the material used for the grade 8 self tapping screws? The grade 8 self tapping screws are depending on what material used for the supplier. If it is common low-carbon steel material, the strength grade of the grade 8 self tapping screws will not meet grade 8, and the maximum of 6.8 self-tapping screws can be achieved. In the Shi Shi Tong, the material of the medium carbon steel 10B21 or the high-carbon steel SCM 435 can be chosen, and after the hard heat treatment, the strength grade is determined to be 8 or even higher grade. Grade 8 self tapping screws , the standard should be grade 8.8 self tapping screws, meaning that the tensile strength of the tapping screw is 800Mpa, and the yield strength is 800×0.8=640Mpa. In order to achieve 8 grade self-tapping screws, the most basic one should also choose 10B21 medium carbon steel material. Some factories choose carbon steel 1018, the surface hardness can reach 8 grades, but the core hardness can not meet the requ...