一种含Ti冷轧热处理双相钢的组织性能研究

介绍了含0.085%Ti微合金元素的780 MPa级冷轧热处理双相钢的试制工艺流程,观察和测试了试验钢的组织,织构和性能,并与相关学者的类似研究做了比较.结果表明:试验钢经过连退工艺后,获得了多边形铁素体和分布在铁素体晶界上的岛状马氏体组织,并有少量贝氏体存在;Ti的添加有细晶强化和沉淀强化的作用,经连退热处理后试验钢的强度达到780 MPa级,拉伸时铁素体中的TiC颗粒钉扎和阻碍位错运动,试验钢出现屈服平台;连退后试验钢组织中铁素体晶粒间多为大角度晶界,且α纤维织构较强,γ纤维织构较弱.

Study on Microstructure and Property of Cold Rolled and Heat Treated DP Steel Microalloyed with Titanium

The pilot production process of 780MPa cold rolled and heat treated DP steel with Titanium was introduced. Microstructure, texture and property of tested steel were investigated, furthermore compared with similar research of other people. The measurement results behind continuous annealing show that microstructure is composed of polygonal ferrite matrix and island martensite and a few bainite. Ti contributes to strength through refining grain and precipitation strengthening mechanism and tested steel’s tensile strength is up to 780MPa. Discontinuous yield appearance during tensile testing is correlated with TiC pinning and hampering dislocation movement. Large angle boundaries are chief among ferrite grains and α-fibers are much more than γ-fibers.