What are the current hex head bolt materials?
At present, the hexagon socket screws on the market mainly include carbon steel, stainless steel and copper.
(1) Carbon steel. We distinguish low carbon steel, medium carbon steel and high carbon steel as well as alloy steel with carbon content in carbon steel.
1, low carbon steel C% ≤ 0.25% domestically known as A3 steel. Foreign countries are basically called 1008, 1015, 1018, 1022 and so on. It is mainly used for products with no hardness requirements such as 4.8 bolts, 4 grade nuts, Socket head cap screws
(Note: 1022 material is mainly used for drilling tail nails).
2. Medium carbon steel is 0.25% and 0.45%. Currently it is basically not used in the market.