温成形中锰钢的组织性能评价

 热成形零件已在汽车安全件上广泛应用，为了进一步提升零件碰撞安全性、提高表面质量、降低成本，基于中锰钢提出了一种降低加热温度的热成形技术，通过将完全奥氏体化的中锰钢在模具中淬火成马氏体组织获得超高强度力学性能，与22MnB5钢热成形相比，在获得1 500 MPa抗拉强度时，中锰钢温成形的加热温度可降低150 ℃以上，断后伸长率提高30%以上，同时提高零件的表面质量。综述并评价了中锰钢经温成形后的微观组织与力学性能以及冷弯性能、成形性能、电阻点焊等工艺性能，并与22MnB5钢热成形进行了系统地比较，体现出温成形中锰钢节能环保、提高碰撞安全性的技术优势。

Evaluation of microstructure and properties of warm #br# stamped medium manganese steel

Hot stamping parts have been widely used in automotive safety parts，in order to further enhance the impact safety of parts，improve surface quality and reduce cost，a kind of hot stamping technology based on medium manganese steel is proposed to reduce heating temperature，ultra high strength mechanical properties were obtained by quenching completely austenitized medium manganese steel into martensite inside die. Compared with the hot stamped 22MnB5 steel，the heating temperature of warm stamped medium manganese steel decreases by more than 150 ℃ when obtains the tensile strength of 1 500 MPa，the plasticity increases by more than 30%，and the surface quality of parts is improved. The microstructure，mechanical properties，cold bending properties，TFLC and resistance spot welding of warm stampede medium manganese steel were reviewed and evaluated. The results were compared with those of hot stamping 22MnB5 steel. It shows the technical advantages of warm forming of medium manganese steel in energy saving，environmental protection and improving collision safety.