取向硅钢常化及其对二次再结晶影响的研究进展

Research progress in normalizing of grain-oriented silicon steel and effect on secondary recrystallization

取向硅钢是重要的铁芯材料,而常化是目前生产高磁感取向硅钢不可或缺的工业生产工序,它可以调整热轧板的组织、织构和抑制剂析出从而改善硅钢磁性能。本文综述了取向硅钢热轧与常化组织的遗传性规律与常化过程中抑制剂的演变规律,重点讨论了常化对初次再结晶和二次再结晶组织与织构的影响规律,指出常化组织中细小γ-晶粒群有利于二次再结晶,而大的变形α-晶粒与λ-晶粒不利于二次再结晶。最后针对低温加热渗氮型高磁感取向硅钢推荐了能最优化磁性能的三段式常化工艺及其参数。而如何在保证获得同等织构组分与抑制剂含量的基础上进一步简化工艺以及常化工艺在薄板坯连铸连轧和薄带连铸生产取向硅钢中的合理应用将是未来常化发展的重点方向。

The grain-oriented silicon steel is an important iron core material,and normalization is an indispensable industrial production process for the production of high magnetic induction grain-oriented silicon steel at present.It can adjust the structure,texture and inhibitor precipitation of hot-rolled band to improve the magnetic properties of silicon steel.The inheritance from hot rolled microstructures to normalized ones of grain-oriented silicon steel and the evolution law of inhibitor during the process of normalizing were summarized,and the influence of normalizing on the microstructure and texture of primary recrystallization and secondary recrystallization was mainly discussed.It is pointed out that the fineγ-oriented grain colonies formed during normalizing favour the final secondary recrystallization whilst the coarse and deformedα-/λ-oriented grains disfavour it.Finally,a three-stage normalization process and its parameters for optimizing magnetic properties of low-temperature heating nitriding type high magnetic induction grain-oriented silicon steel were recommended.The key research direction of normalizing in the future is to further simplify process on the basis of ensuring the same texture and inhibitor content,and rational application of normalizing process in the grain-oriented silicon steel produced by thin slab casting and rolling and strip casting.