How to choose the material of U-shaped bolts
The material of the bolt may have to consider the hardness and strength of the bolt when it is of special use. When selecting bolts, data issues must be considered. At present, the standard bolt materials on the market mainly include carbon steel bolts, stainless steel bolts, and copper bolts.
(1) Carbon steel. We distinguish low-carbon steel, medium-carbon steel, high-carbon steel and alloy steel by the carbon content of carbon steel. 1. Low carbon steel C%≤0.25% is generally called A3 steel in China. It is basically called 1008, 1015, 1018, 1022, etc. abroad. It is mainly used for products with no hardness requirements such as grade 4.8 bolts, grade 4 nuts, small screws, etc. (Note: 1022 data is mainly used for drill tail nails.) 2. Medium carbon steel 0.25% 0.45%. Nowadays, it is not used at all in the market. 4. Alloy steel: Add alloy elements to ordinary carbon steel, and add some special functions of steel: such as 35, 40 chromium molybdenum, SCM435, 10B38. Fangsheng screws mainly use SCM435 chromium-molybdenum alloy steel, the main components are C, Si, Mn, P, S, Cr, Mo.
(2) Stainless steel. Functional grade: 45, 50, 60, 70, 80, mainly divided into austenite (18%Cr, 8%Ni), good heat resistance, good corrosion resistance, and good weldability. A1, A2, A4 martensite and 13%Cr have poor corrosion resistance, high strength and good wear resistance. C1, C2, C4 ferritic stainless steel. 18%Cr has better upsetting and corrosion resistance than martensite. At present, the import materials on the market are mainly Japanese products. According to the level, it is mainly divided into SUS302, SUS304, and SUS316.
(3) Copper. Commonly used materials are brass zinc-copper alloy. In the market, H62, H65, and H68 copper are mainly used as standard parts.