关键词：热力学参数；含Al的AHSS；相馏分；转变温度
摘 要：To predict phase equilibria of advanced high strength steels accurately,a new multicomponent thermodynamic database (FEDA) encompassing Fe,C,Mn,Si,Al and Ni is created according to relevant literatures.This study applies Thermo-Calc software to estimate phase transformation temperatures and phase fractions in ferrite and austenite two-phase region of test steels.Simultaneously,experiments are carried out with dilatometer and the quantitative metallographic analysis technology.It is found that the FEDA database is appropriate for predicting A/temperature and phase fractions of Al-containing steels at low temperatures,while the TCFE6 database can be used to estimate A3 temperature.According to calculated phase fractions using FEDA database,a two-step heat treatment is made in order to achieve TRIP-aided steels.Samples annealed at 780℃ for 3 min and held at 420℃ for 5 min exhibit an optimum value of strength and ductility product up to 23690 MPa.％.