In recent years, the automobile industry at home and abroad has been implementing lightweight automobile to save energy, and it is urgent to replace solid parts with high-strength hollow parts.It is technically feasible to develop high strength steel tubes instead of seamless tubes to meet the needs of the automobile industry.In the development of high-strength steel tubes for automobile industry, Japan has successively developed c-TI-B, C-MN-NB, C-CR-AI-B and other steel series, and adopted different heat treatment systems according to different purposes, such as annealing, normalizing, quenching and tempering.Used for high strength steel pipe in automobile industry, its standard strength classes are 561MPa, 637MPa, 980MPa, etc.In addition to the requirements of high strength, the steel pipe also requires high plasticity, good processing, hardenability, strong toughness and fatigue strength.