微量稀土铈对IF钢再结晶行为的影响

Effect of micro-content cerium on recrystallization behavior of IF steel

利用热压缩试验的方法,在Gleeble-1500D型热模拟试验机上进行单、双道次压缩试验,研究了不同变形条件下微量稀土铈对IF钢再结晶行为的影响,分别绘制了铈添加前后试验钢在应变速率0.1-10 s-1,变形温度950℃,压缩变形50%的单道次真应力-真应变曲线以及不同道次间隔时间1-100 s,变形温度950℃,两道次压缩变形量均为30%的双道次真应力-真应变曲线。结果显示：950℃压缩变形时,应变速率低于1 s-1时,稀土铈对试验钢动态再结晶的抑制作用较明显;试验钢静态再结晶体积分数随道次间隔时间的延长而增加,稀土铈抑制试验钢静态再结晶的进行;稀土铈对晶界的拖拽作用是稀土抑制再结晶行为的主要机制。

The effects of cerium on the recrystallization behavior of IF steel under different forming conditions were investigated by single and double compression tests on a Gleeble-1500 D thermo-mechanical simulator with the method of isothermal compression test.The true stress-strain curves of the tested steel with and without Ce were drawn at temperature 950 ℃,strain rate 0.1 - 10 s-1,deformation of50% for single compression and the interval time from 1 to 100 s,at temperature 950 ℃,deformation of 30% for double compression.The results show that dynamic recrystallization is obviously restrained at temperature of 950 ℃ and the strain rate less than 1 s-1,static recrystallization volume fraction is increased with the prolonged interval time and static recrystallization behavior is depressed for the steel with addition of Ce.The drag effect on grain boundary is the main mechanism of cerium＇s inhibition on recrystallization behavior.