20 # material is a high-quality low-carbon carbon steel, cold-extruded, carburized and hardened steel. SA588 Grade B asme low alloy steel, 20 # material has low strength, good toughness, plasticity and good weldability. Chemical composition of 20 # round steel bar: C: 0.17 ~ 0.23, Si: 0.17 ~ 0.37, Mn: 0.35 ~ 0.65, S: ≤0.035, P: ≤0.035, Cr: ≤0.25, Ni: ≤0.30, Cu: ≤0.25. 20# carbon steel mechanical properties: Shear strength 275 ~ 392MPa, Tensile strength is 253 ~ 500MPa, elongation min. 25%.
The toughness of steel such as SA588 Grade B asme low alloy steel is the ability of steel to absorb energy in the process of plastic deformation and fracture, and also the ability of steel to resist impact load. It is related to and different from the plasticity of steel. It is the comprehensive performance of strength and plasticity. The strength plasticity index of steel is obtained by static tensile test. When these indexes are used to bear the dynamic load structure, there are obvious limitations.
After 1975, our equipment includes blast furnaces, electric furnaces, vacuum refining furnaces, and electroslag furnaces. The product varieties are relatively complete. Plates, SA588 Grade B asme low alloy steel tubes, wires, belts, and profiles have a certain scale, including magnetic, elastic, expanded, bimetal and other precision alloy materials for national defense and electronics industries. In 1982, these plants produced 364,000 tons of SA588 Grade B asme low alloy steel steel and 542,000 tons of steel.