初次再结晶组织和渗氮量对低温渗氮取向硅钢二次再结晶行为的影响

Effect of Primary Recrystallized Microstructure and Nitriding on Secondary Recrystallization in Grain Oriented Silicon Steel by Low Temperature Slab Reheating

通过控制初次再结晶工艺获得尺寸不同的低温渗氮取向硅钢初次再结晶组织,研究初次晶粒尺寸对二次再结晶行为和磁性能的影响,探索初次晶粒尺寸过大条件下合适的渗氮量,并分析初次再结晶组织中{411}〈148〉织构对二次再结晶行为的影响。结果表明:随着初次晶粒尺寸由10μm升高至15μm,二次再结晶温度升高,Goss织构更加锋锐,成品磁性能提高,当初次晶粒尺寸为28μm时,合适的渗氮量约为6×10-4。初次再结晶组织中{411}〈148〉取向晶粒生长能力更强,极易粗化,阻碍二次晶粒的异常长大,同时{411}〈148〉与黄铜晶粒之间为大于45°的低迁移率晶界,对黄铜晶粒异常长大的阻碍作用更为显著。

Different primary recrystallized grain sizes were obtained by controlling decarburization process in grain oriented silicon steel produced by low temperature slab reheating technique. The effect of primary grain size on secondary recrystallization and magnetic properties was studied. The appropriate nitrogen content after nitriding was explored in case of very large primary grain size, and the effect of { 411} 〈 148） primary recrystallized texture on the abnormal growth behavior was dis-cussed. The results show that an increase in average primary grain size from10jLtm to 15jLtm leads to an increase of secondary recrystallization temperature and a sharper Goss texture with higher magnetic permeability, in the condition of a very large average primary grain size of 28jLtm, the suitable amount of nitrogen increases to about 6 10 -4. The {411} 〈 148） oriented grains in primary recrystallized mi-crostructure can easily grow into larger sizes due to their size advantage, and thus hinder the abnormal growth of secondary grains, moreover, the hindering effect is more pronounced in the abnormal growth of Brass-oriented grains due to their misorientation with low migration rate other than Goss grains.