中温含铜取向硅钢的形变和再结晶织构特征

Deformation and recrystallization texture features of medium temperature reheated grain oriented silicon steel containing copper

通过对比中温含铜取向硅钢与普通取向硅钢和高磁感取向硅钢的组织和织构特征,分析中温含铜取向硅钢独特的织构演变规律及其对二次再结晶行为的影响.结果表明,为了获得有利于高斯晶粒长大的强γ取向线织构,中温含铜钢需经过回复退火处理和高温退火阶段慢速升温.回复过程中γ取向线晶粒储能降低,同时慢速升温有利于γ取向线晶粒的形核和再结晶.中温含铜钢的二次再结晶开始温度超过1000℃,由于初次再结晶晶粒组织以γ织构为主且非γ取向线晶粒较少,导致最终二次晶粒尺寸超大且晶界圆滑,二次再结晶机理以择优长大为主导,超大的二次晶粒尺寸导致最终成品的铁损升高,但通过激光刻痕处理后,整体铁损的降低效果比二次晶粒较小的高磁感取向硅钢更加显著.

The unique texture evolution and secondary recrystallization behavior of medium temperature reheated grain oriented silicon steel containing copper were analyzed by comparison with those of conventional grain oriented silicon steel and high permeability silicon steel.The results show that to obtain a stronger γ-fiber primary recrystallization texture,which can be easily consumed by Goss grains,recovery annealing and slow heating rate of high temperature annealing are necessary.During the high temperature annealing stage,the strong γ-fiber primary recrystallization texture shows the effects of decreasing the stored energy caused by recovery annealing and increasing the nucleation rate of γ-fiber grains with slow heating rate.The onset temperature of secondary recrystallization exceeding 1000 ℃ and the strong γ-fiber primary recrystallization texture with less non-γ-fiber oriented grains indicate that the secondary recrystallization behavior is dominated by preferred grain growth.As a result,very huge secondary recrystallization grains with smooth boundaries are obtained.The iron loss is increased due to huge secondary grain size characterized in medium temperature reheated grain oriented silicon steel final products,but can be reduced significantly by magnetic domain refinement using laser scribing,compared with that of high permeability grain oriented silicon steel with small secondary grain size.