Fe-3.15%Si低温取向硅钢不同常化工艺下的组织及析出相研究

STUDY ON MICROSTRUCTURE AND PRECIPITATES AT DIFFERENT NORMALIZING IN Fe-3.15%Si LOW TEMPERATURE ORIENTED SILICON STEEL

利用OM,TEM,EDS与XRD技术,对Fe-3.15%Si低温取向硅钢热轧板不同常化处理后的显微组织、析出相及最终产品的磁性能进行了分析研究,并对热轧板和常化板经过冷轧后的冷轧板织构进行了对比分析.结果表明,采用1120℃保温3 min二段式冷却的常化处理工艺,常化板表层显微组织均匀,沿板厚方向的显微组织的不均匀性显著,对后续过程中形成高取向的Goss织构最有利,取向硅钢的磁性能最高;采用二段式冷却的常化冷却工艺最优,在此冷却工艺下析出的细小的析出物数量最多,且弥散分布在基体中,抑制剂的抑制效果最好,对成品获得高磁性最有利;热轧板、常化板经过冷轧后的冷轧板织构均主要由{111}〈110〉和{111}〈112〉织构组成,但常化板较热轧板冷轧后的冷轧板γ取向线织构密度明显增高,由此可以证实常化处理有助于取向硅钢最终获得高取向的Goss织构.

The decreasing of slab heating temperature for grain-oriented silicon steel will reduce the amount of precipitates in hot rolled plate, and be disadvantage to the formation of ultimate Goss texture. The aim of normalizing is to control and adjust the amount, size and distribution of precipitates. Microstructures, precipitates and magnetic characteristics of finished products with different normalizing technologies for Fe-3.15%Si low temperature hot rolled grain-oriented silicon steel are researched, and the textures of cold rolled plates which are original hot rolled plate and normalized plate are analyzed by means of OM, TEM, EDS and XRD, respectively. The results show that, normalizing technology with a temperature of 1120℃, holding 3 min, and a two stage cooling is a most advantaged to obtain oriented silicon steel with sharper Goss texture and higher magnetic, owing to the uniform surface microstructures and the obvious inhomogeneity of microstructures along the thickness; the normalizing technology with two-stage cooling is the optimum process, which due to more finer precipitates are dispersively distributed in the matrix, and it is beneficial for finished products to get a higher magnetic; in these two processes, they obtain the same textures which are mainly consist of {111}（110） and {111}（112）, however, comparing with the cold rolled textures without normalizing, the textures density of У orientation line on cold rolled plate which treated by normalizing are significantly increased. Therefore, it is confirmed that normalizing is helpful for grain-oriented silicon steel to get sharper Goss texture.