20mm薄板坯试制高牌号无取向硅钢的组织性能研究

Study on Structure and Property of High Grade Non-Oriented Silicon Steel Sheet via 20 mm Thin Slab

采用薄板坯工艺制备了厚度为20 mm的2.9%Si-0.77%Al无取向硅钢铸坯,经热轧、常化、冷轧、退火后,对其显微组织、析出物、磁性能进行了检测分析,结果表明：铸带为穿晶组织,热轧板表层为细小的再结晶晶粒,中心层为粗大的变形晶粒,热轧板常化后再结晶完全,成品板为等轴晶组织。成品析出物主要是Al N和（Mn S＋Al N）复合析出物,尺寸较粗大,为0.5~2.5μm。成品磁性能为P15=2.86 W/kg,B50=1.70 T。

2. 9% Si- 0. 77% Al non-oriented silicon steel slab had been produced by the thin slab process with a thickness of 20 mm. After hot rolling,normalizing,cold rolling and annealing,the resulting sheet had been investigated in terms of microstructure,precipitates and magnetic properties. The results show that thin casting slab has a typical transcrystalline grain structure,while the structure of hot rolled strip comprising of fine recrystallized grain at edge and coarse deformed structure in the center. Normalizing process leads to a fully-recrystallized microstructure,and finished sheet is characterized by an equaixed grain microstructure. The precipitates are dominant coarse Al N and（ Mn S ＋ Al N） composite in size of 0. 5~ 2. 5 μm. The magnetic property of resulting silicon steel are P15= 2. 86 W / kg and B50= 1. 70 T.