中文摘要：

通过Gleeble-1500D型热模拟试验机,测定了Ti-IF钢和Ti＋Ce-IF钢在变形温度为790、950℃,变形速率为0.1、1、5和10 s-1时的应力-应变曲线;并使用金相显微镜对空冷后的变形组织进行观察。结果表明：Ce不改变变形速率对IF钢流变应力和显微组织的影响规律;Ti-IF钢和Ti＋Ce-IF钢在790℃和950℃变形时,流变应力均随变形速率的增大而增大,Ti＋Ce-IF钢的流变应力值比Ti-IF钢高;变形速率越高,晶粒变得越粗大;低温变形时,晶粒中伴有纤维状组织,呈现出轧制态晶粒特征;在790℃、0.1 s-1变形时,Ti-IF钢和Ti＋Ce-IF钢均易于获得均匀的晶粒组织,有助于提高综合力学性能的稳定性。

英文摘要：

Strain-stress curves of Ti-IF and Ti ＋ Ce-IF steel were drawn by Gleeble-1500D thermal mechanical simulator with deformation temperature 790 ℃ and 950 ℃,strain rate of 0. 1,1,5 and 10 s-1,deformation of 50%. And the microstructure was observed by metallographic microscope. The results show that Ce does not change the deformation rate of the IF steel flow stress and microstructure of the influence law. Flow stress increases with the increase of deformation rate both Ti-IF and Ti ＋ Ce-IF steel at 790 ℃ and 950 ℃,and the flow stress of Ti＋Ce-IF steel is higher than Ti-IF steel. The higher deformation rate,the larger grain becomes. Accompanied by fibrous tissues in the grain,both steels show the characteristics of rolling state grain with low temperature deformation. Under the condition of 790 ℃,with 0. 1 s-1 strain rate both Ti-IF steel and Ti＋Ce-IF steel are easy to obtain uniform grain structure,which helps to improve the stability of the comprehensive mechanical properties.