退火时间对中锰热轧TRIP钢组织演变的影响

为了研究热轧Fe-6Mn-3Al TRIP钢组织演变和力学性能,对实验钢采用淬火+不同时间退火(ART)的热处理工艺.研究发现,随着退火时间的增加,奥氏体晶粒尺寸增大、稳定性降低,冷却过程中部分奥氏体相变为马氏体;其中退火10 min后,实验钢性能最优,其残余奥氏体体积分数能达到50.3%,抗拉强度765 M Pa,总延伸率达到49.1%;拉断后实验钢中的奥氏体含量减少,马氏体含量增加,其中,退火10 min后的实验钢TRIP效应最为明显,奥氏体体积分数由变形前的50.3%降低到变形后的11%,奥氏体转化率为78%.

Influence of Annealing Time on the Microstructure EVolution in the Medium-Mn Hot-Rolled TRIP Steel

Microstructure evolution and mechanical properties of a hot-rolled Fe-6Mn-3Al TRIP steel were studied by using the heat treatment process of quenching and annealing for different time (ART). The results showed with the increase of annealing time， the grain size of austenite increases and the stability decreases. Part of the austenite transforms into martensite in the cooling process. After annealing for 10min， the performance of the experimental steel is optimal. The volume fraction of austenite is 50.3%， the ultimate tensile strength is 765MPa and the total elongation is 49.1%. The content of the austenite decreases and the martensite increases after deformation. The TRIP effect is most obvious after annealing for 10 min. The volume fraction of austenite reduces from 50.3% to 11% after deformation. The transformation rate of austenite is 78%.