【摘要】 化学成分和热处理工艺是影响TRIP钢力学性能的关键因素。通过热模拟试验方法研究了不同成分试验钢在临界区退火过程中的微观组织变化规律。结果表明:随着两相区退火温度的升高,铁素体平均晶粒尺寸逐渐减小,铁素体体积分数随着加热温度的升高而降低;残余奥氏体量和其中的C质量分数先随着退火温度的升高而降低,达到一个低谷以后,再随退火温度的升高而升高;在相同的退火温度下,随着Nb的加入,多边形铁素体晶粒尺寸细化,铁素体体积分数逐渐减少;既加Nb又高Si的试验钢钢中残奥数量最多,不加Nb的试验钢中残奥数量最少。TRIP钢试制结果表明,钢带组织类型为典型的TRIP钢组织,多边形铁素体平均晶粒尺寸约8μm,体积分数67%,残余奥氏体体积分数为5.58%,残余奥氏体中C质量分数为1.34%,同时,力学性能也完全满足TRIP590的性能要求。更多还原

【Abstract】 The effects of chemical composition and critical annealing temperature on the microstructure and mechanical properties of TRIP590 steel were investigated by utilizing thermal simulation.The results show that the average grain size and the volume fraction of ferrite both decrease as the annealing temperature increases,while the volume fraction of retained austenite and C concentration in austenite firstly decrease and then increase.At the same annealing temperature,the volume fraction and the average grain size of ferrite both decrease with increasing Nb content.There is maximum volume fraction of retained austenite in the highest Nb and Si content steel,while minimum in Nb-free steel.Industrial trial results show that the microstructure type of the strip is ferrite,bainite and retained austenite,at the same time,the mechanical properties can meet the performance requirements.更多还原