以碳含量为12 mg·kg-1的超低碳IF钢为研究对象, 利用Gleeble3500型热模拟试验机结合硬度测量和显微组织观察等方法研究了冷轧压下率和退火工艺对其再结晶和力学性能的影响。结果表明: 经历75%, 79%和84%压下率冷轧后, 试验用钢的再结晶温度分别为691, 688, 685 ℃, 低于碳质量分数为0.002 4%IF钢的, 且随冷轧压下率的增大, 再结晶温度略有下降; 随退火温度升高, 其强度降低, 伸长率升高; 以830 ℃进行连续退火工业生产为例, 保温时间在60～180 s范围可保证再结晶完成。

Regarding ultra-low carbon IF steel with carbon content of 12 mg·kg-1 as the research subject, effects of cold rolling reduction and annealing process on recrystallization and mechanical properties of ultra-low carbon IF steel were studied by Gleeble3500 thermal simulation test machine combined with other experiment methods such as hardness test and microstructure observation. The results show that with different rolling reductions of 75%, 79% and 84%, the recrystallization temperatures of tested steel were 691, 688 and 685 ℃ respectively, which were a little lower than that of the IF steel with carbon content of 0.002 4wt%. The recrystallization temperature decreased a little with the increase of cold rolling reduction rate. The strength decreased and elongation raised with the increase of annealing temperature. To take annealing at 830 ℃ as an example, the holding time of 60-180 s could ensure recrystallization completion.