Classification of carbon steel rods

Carbon steel can be divided into low carbon steel, medium carbon steel and high carbon steel according to chemical composition (namely, with carbon content).

(1) Low carbon steel

Also known as mild steel, carbon content from 0.10% to 0.30% mild steel is easy to accept various processing such as forging, welding and cutting, often used in the manufacture of chains, rifts, bolts, shafts, etc.

(2) Medium carbon steel

Carbon steel with 0.25% ~ 0.60% carbon content. There are sedative steel, semi-sedation steel, boiling steel and other products. "In addition to carbon, it may contain a small amount of manganese (0.70%-1.20%)." According to product quality, it is divided into ordinary carbon structural steel and high quality carbon structural steel. Hot working and cutting performance is good, welding performance is poor. The strength and hardness are higher than low carbon steel, while the plasticity and toughness are lower than low carbon steel. Without heat treatment, direct use of hot rolled materials, cold drawn materials, can also be used after heat treatment. After quenching and tempering, the medium carbon steel has good mechanical properties. The maximum hardness that can be achieved is about HRC55(HB538), and σb is 600 ~ 1100MPa. Therefore, among the various uses at moderate strength levels, medium carbon steel is the most widely used, in addition to being a building material, it is also widely used in the manufacture of various mechanical parts.

(3) High carbon steel

Commonly known as tool steel, carbon content from 0.60% to 1.70%, can be quenched and tempered. Hammer, crowbar, etc. are made of steel with 0.75% carbon content; Cutting tools such as drills, taps, reamers, etc. are made of steel with a carbon content of 0.90% to 1.00%.