冷轧中Mn-TRIP钢的机理与研发进展

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

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Ltiders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。l000一l200MPa级冷轧中Mn—TRIP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35GPa·％，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。

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, Ltiders 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.