Mild steel is a carbon steel with carbon content less than 0.25%. It is also called mild steel because of its low strength, low hardness and soft. It includes most common carbon structural steels and part of high quality carbon structural steels, most of which are used for engineering structural parts without heat treatment, and some of which are used for mechanical parts requiring wear resistance after carburizing and other heat treatment.
Low carbon steel annealed structure is ferrite and a small amount of pearlite, its strength and hardness is low, plasticity and toughness is better. Therefore, its cold formability is good, can be used edge rolling, bending, stamping and other methods for cold forming. The steel also has good weldability. Low carbon steel generally refers to the carbon content between 0.10 ~ 0.25% of the steel. This kind of steel has low hardness and good plasticity, which is convenient for the use of cold plastic deformation forming process, welding and cutting, and is often used in the manufacture of self-lubricating bearing bushings