普通取向硅钢组织及织构的演变特征

Evolution characteristics of microstructure and texture of CGO steel

采用光学显微镜、EBSD观察并研究了普通取向硅钢组织、织构的演变特征。结果表明:热轧板组织及织构沿板厚方向存在不均匀性,一次冷轧后,组织发生了较大变化,完全转变为纤维带状条带组织。经840℃×10 min脱碳退火后初次再结晶晶粒平均尺寸为20.13μm,织构主要有{001}<010>、{111}<112>、以及Goss等织构,并可将碳脱至3.5×10-5以下。二次冷轧后,组织再次转变为纤维带状组织,织构类型与一次冷轧板织构类型类似,仅织构强度不同。经650℃×4 min回复时,冷轧组织发生了完全再结晶,再结晶晶粒平均尺寸为7.25μm。高温退火过程中,随着温度的升高,具有Goss位向的初次晶粒发生异常长大,温度到达1000℃时,晶粒尺寸达到厘米级,成品晶粒平均直径为18.92 mm,晶粒较为圆整,成品最佳磁感为1.885 T,铁损为1.21 W/kg。

Evolution characteristic of microstructure and texture of a conventional grain-oriented （CGO） steel was studied by metallurgical microscope and EBSD technique. The results show that the microstructure and texture are inhomogeneous along the thickness direetion in the hot rolling slab of the CGO steel. After the first cold rolling, the microstructure of the hot rolling slab is changed significantly, and then many fibrous bands are generated. These fibrous bands almostly disappeared after decarburizing annealing at 840 ℃ for 10 min, the earbon content is down to 3.5 × 10 5, and the average grain size is 20. 13 μm. Its mainly texture is cube texture [001] 〈010 〉 , [ 111 ] 〈 112 〉 and Goss texture. Especially, the recrystallized grains are elongated by the second cold rolling, and its texture type is similar to that of the first cold rolling, only existing different values on the texture density. The complete recrystallization of the cold rolling slab occurred after recovery heat treatment at 650 ℃ for 4 min, for which the average grain diameter is 7.25 μm. During the high temperature annealing, the recrystallized grains with Goss orientation abnormally grow up to be secondary recrystallized grains by swallowing other oriented grains. While the temperature increases to 1000 ℃ , the average grain size is up to centimetre-level, and the average grain size of the final product is 18.92 mm, the optimal magnetic induction is 1. 885 T and the iron coss is 1.21 W/kg.