Hex Bolt Manufacturers introduces 3 materials for bolts:

1. Carbon steel. We distinguish low carbon steel, medium carbon steel and high carbon steel, and alloy steel by the content of carbon in carbon steel material.

①Low carbon steel C%≤0.25% is usually called A3 steel in China. Foreign countries are basically called 1008, 1015, 1018, 1022, etc. Mainly used for grade 4.8 bolts, grade 4 nuts, small screws, and other products without hardness requirements.

②Medium carbon steel 0.25%<C%≤0.45% is usually called No. 35 and No. 45 steel in China and is basically called 1035, CH38F, 1039, 40ACR, etc. abroad. Mainly used for grade 8 nuts, grade 8.8 bolts, and grade 8.8 hexagon socket products.

③ High carbon steel C%>0.45%. Currently not used in the market

④Alloy steel: Add alloying elements to ordinary carbon steel to increase some special properties 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, and Mo.

2. Stainless steel.

Performance Class: 45, 50, 60, 70, 80 Mainly divided into austenite (18%Cr, 8%Ni) with good heat resistance, good corrosion resistance, and good weldability. A1, A2, and A4 martensite, 13%Cr have poor corrosion resistance, high strength, and good wear resistance. C1, C2, C4 ferritic stainless steels. 18%Cr has better upsetting and corrosion resistance than martensite.

3. Copper. Commonly used materials are brass...zinc-copper alloys. The market mainly uses H62, H65, and H68 copper as standard parts.