高强韧QPT工艺的先进钢组织调控和强韧化研究进展

Research Progress of Microstructure Control and Strengthening Mechanism of QPT Process Advanced Steel with High Strength and Toughness

先进高强钢经历了从第一代至第三代的高速发展,为汽车工业中轻量化及安全性的持续提升提供了重要保障。作为第三代先进高强钢的代表钢种之一,淬火-配分(QP)钢和淬火-配分-回火(QPT)钢近10年来发展迅速。本文从以下几个方面对QP钢及QPT钢的制备工艺和强韧化机理进行了综述:(1)从QP到QPT的工艺设计发展历程及其原理;(2)配分过程中的C配分和组织演变规律;(3)亚稳奥氏体的稳定性及其对相变诱发塑性(TRIP)效应的影响;(4)纳米析出强化的QPT钢的组织和热处理工艺设计;(5)热成形QPT钢一体化工艺;(6)QP钢、QPT钢的强韧化机制和使用服役性能。并对今后QP钢和QPT钢的制造与使用前景作出展望。

Advanced high-strength steels have undergone rapid development from the first to third generation,which has considerably contributed to the continuous improvement of lightweight materials and safety in the automotive industry.The third generation representative steels,including quenchingpartitioning(QP)and quenching-partitioning-tempering(QPT)steels have rapidly developed in the past 10 years.This article summarizes the preparation process as well as the strengthening and toughening mechanisms of QP and QPT steels from the following perspectives:(1)process design development and principles from QP to QPT,(2)carbon distribution and microstructure evolution during the partitioning process,(3)stability of metastable austenite and its influence on transformation-induced plasticity,(4)microstructure and heat-treatment process design of nanoprecipitation-strengthened QPT steel,(5)the integrated process of hot-forming QPT steel,and(6)the strengthening and toughening mechanisms and the service performance of QP and QPT steels.Finally,future prospects for manufacturing and using QP and QPT steels are discussed.