A comprehensive overview of high strength and toughness steels for automobile based on QP process
Shaobin Bai, Yongan Chen, Jian Sheng, Dazhao Li, Hui‐Hu Lu, Peikang Bai, Zhiquan Huang, Jingyang Li, Chao Zhao
Abstract
High-strength steels support the rapid development of modern automobile industry. Especially quenching-partitioning (QP) steels have presented the considerable potential thanks to their excellent mechanical properties. In recent years, quenching-partitioning-tempering (QPT), as well as other processes developed from QP process (DF-QP processes), have received much attention. Numerous QP and QPT steels have been widely used in automobile body materials. This paper summarizes the design principles of QP, QPT, and DF-QP processes of the latest research progress on microstructures and mechanical properties of the high-strength and toughness steels. Furthermore, three key aspects, involving of (i) the carbon (C) partitioning behavior during heat-treatment process and its influence on austenite stability, (ii) the internal relationship between austenite stability and deformation mechanism, and (iii) the influence of micro-alloying elements on microstructure, are summarized in the QPT steels. Finally, the service performances of above-mentioned steels are evaluated and their development prospects are forecasted.