冷变形量对低碳冷轧板组织及再结晶温度的影响

Effect of Deformation on Microstructure and Recrystallization of Low Carbon Cold Rolled Sheet

对不同冷变形量的低碳冷轧板,在不同温度下进行模拟罩式退火试验,研究了冷变形量对组织和再结晶温度的影响。分析比较发现,随冷变形量提高,加工硬化效果增强,位错密度增加;在650℃×4 h退火后,随着冷变形量的增大,再结晶晶粒更加细小且均匀。通过推导得到了再结晶驱动力与冷变形量的关系式,并计算出不同冷变形量的再结晶驱动力。结果表明,当冷变形量从52%增加到80%后,由位错密度产生的再结晶驱动力提高1.4×104J/m2;其再结晶开始温度和完成温度均降低20～40℃。

Simulated bell-type furnace annealing test of cold rolled sheet with different reduction ratio was carried out under different temperatures. The results show that strain hardening effect and dislocation density increase as cold reduction increases. the recrystallized grain size is much finer and uniform after annealing at 650 ℃ for 4 h. Recrystallization driving force as function of deformation was derivated and then being used to calculate value of recrystallization driving force. Calculation shows that when cold reduction increases from 52% to 80%,recrystallization driving force produced by the dislocation density increased by 1.4×10^4J /m^2,and both starting and complete recrystallization temperature decrease at 20～40 ℃.