热变形对Fe-3%Si钢软化率的影响及其组织表征  

Effect of Hot Deformation on Softening Fraction of Fe-3%Si Steel and Its Microstructure Characterization

作　　者：于永梅 胡亮明 彭加利 李长生[2] 王国栋[2] YU Yongmei;HU Liangming;PENG Jiali;LI Changsheng;WANG Guodong(Mechanical Engineering School, Shenyang University of Chemical Technology, Shenyang 110142, China;State Key Lab of Rolling and Automation, Northeastern University, Shenyang 110819, China)

机构地区：[1]沈阳化工大学机械工程学院,辽宁沈阳110142 [2]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819

出　　处：《热加工工艺》2018年第10期34-38,共5页Hot Working Technology

基　　金：国家自然科学基金项目(U1260204,51404155)

摘　　要：采用热力模拟方法对Fe-3%Si钢热变形参数对静态再结晶的影响以及显微组织和晶界特征进行了研究。结果表明,对于单相铁素体硅钢而言,变形（等温）温度越高,应变和应变速率越大,再结晶动力学进程越快。在应变为0.8、应变速率为2 s^-1和等温3000 s条件下,变形（等温）温度从900℃提高到1100℃时,再结晶软化率由28%提高到70%以上。对于含奥氏体的硅钢,热变形参数对软化率的影响与不含奥氏体的硅钢呈现基本相同的规律,但奥氏体的出现增加了材料的再结晶率。对于初始晶粒尺寸为131μm,奥氏体含量为8%的Fe-3%Si钢,会随着退火时间的增长,小角晶界从轧后1 s淬火到轧后退火50 s由24%降至7%。等温时间达到15 s以内,大角晶界明显增加,小角晶界大幅减少。50 s时小于5°的取向差完全消失。The thermal simulation testing was adopted to investigate the effect of hot deformation parameters on the static recrystallization and its microstructure and grain boundary characteristic. The results show that, for single-phase ferritic silicon steel, the higher the deformation（holding） temperature, the larger the strain and strain rate, and the faster the static recrystallization kinetics coures. The softening fraction of the recrystallization increases from 28% to 70% with the increase of deformation temperature from 900 ℃ to 1100 ℃ for the case of strain of 0.8, strain rate of 2 s^-1 and holding time of 3000 s. It has a similar effect of hot deformation variables on recrystallization kinetics for silicon steels with and without austenite, but the presence of austenite significantly increases the recrystallization rate of the material. The fraction of low-angle grain boundaries（LAGBs）of samples quenching for 1 s to 50 s after rolling decreases from 24% to 7% for Fe-3%Si steel with an initial grain size of 131μm and the austenite content of 8%. Prolonging the holding time to 15 s leads to a dramatic decrease in LAGB fraction and increase in the HAGB, respectively. The misorientation less than 5° disappears at the holding time of 50 s.

关 键 词：硅钢 组织 应变 取向 再结晶 

分 类 号：TG335[金属学及工艺—金属压力加工]