冷轧中Mn－TRIP钢的机理与研发进展

中Mn-TRIP钢作为第三代汽车用钢研发的重点,从21世纪初就得到越来越多国内外汽车及钢铁企业的关注。介绍了中Mn-TRIP钢种的最新机理研究与工业化进展。中Mn-TRIP钢主要由纳米级至微米级铁素体和亚稳奥氏体构成,有时也含有一定比例的马氏体,其组织特征和变形机理与其他先进高强钢有显著不同。众多科研院所做了大量工作,包括中Mn成分设计、相变精细结构表征、超细晶Lüders应变行为、相变诱导加工硬化、奥氏体不全位错滑移等,从而对中Mn-TRIP钢有了更为深入的认识。1 000~1 200 MPa级冷轧中MnTRIP钢和热镀锌中Mn-TRIP钢已经成功实现了工业化试制,其强塑积大于35 GPa·%,标志着冷轧中Mn-TRIP钢正逐步由基础研究向工业化生产推进。

Mechanism and development progress of cold-rolled medium Mn-TRIP steel

As one of the most important third generation automotive steels , the medium Mn-TRIP steel has drawn more and more attentions from domestic and foreign automotive and steel enterprises .The latest progress in the mechanism research and development is introduced .Medium Mn-TRIP steel is mainly composed of nanosized to microsized ferrite , metastable austenite and possibly a certain amount of martensite , which is significantly different from other advanced high strength steels in terms of the microstructure characteristics and deformation mechanism .Many academic institutes have done a lot of work , including the Mn component design , phase transformation characterization, Lüders strain of ultra-fine grains, transformation induced work hardening , austenitic partial dislocation slip and so on .Furthermore, 1 000~1 200 MPa cold rolled medium Mn-TRIP steel and hot dip galvanized medium Mn-TRIP steel have been industrialized , and their strength-ductility balance is higher than 35 GPa· %, which reveals that more industrialization application has been performed based on the academic research .