低温板坯加热Hi-B钢的组织和织构演变

Evolution of microstructure and texture for Hi-B steel using low-temperature slab heating

采用光学显微镜和X射线衍射仪对低温板坯加热Hi-B钢的组织、织构的特征演变进行了研究。结果表明:从热轧板和常化板的表面到中心,组织和织构分布不均匀。热轧板组织分为表层再结晶区域、再结晶和变形晶粒混合区域和中心变形晶粒区域,并且热轧板各层的织构类型不同。常化板表层晶粒长大,过渡层和中心层的形变晶粒基本消失,常化板继承了热轧板的织构特点。冷轧板为纤维状变形组织,冷轧后形成了以{001}<110>~{111}<110>为主的α织构。脱碳渗氮板的横断面和纵断面的晶粒平均尺寸分别为25.9μm和25.3μm,织构主要为{111}<112>、{114}<481>和{001}<120>织构。成品板晶粒平均尺寸为19.1μm,成品板为单一的高斯织构。

The evolutions of microstructure and texture for Hi-B steel using low-temperature slab heating technology were studied by optical microscope and X-ray diffractometer. The results show that the distribution of microstructure and texture is not uniform from the surface to the center layer in the hotrolled band and annealed hot-rolled band. The microstructure of the hot-rolled band consists of the surface recrystallized region, the mixed region of recrystallized and deformed grains, and the central deformed grain region. Moreover, the texture types of each layer in the hot-rolled band are different. The grains in the surface layer of the annealed hot-rolled band grow, the deformed grains in the transition layer and the center layer disappear, and the annealed hot-rolled band inherits the texture characteristics of the hot-rolled band. In addition, the cold-rolled band has a fibrous deformed structure. An α texture dominated by {001}<110>~{111}<110> is formed during cold-rolling. The average grain size of the transverse section and vertical section of the decarburized and nitrided sheet is 25.9 μm and 25.3 μm, respectively, and the textures are mainly {111}<112>, {114}<481> and {001}<120> textures. The average grain size of the final product is 19.1 μm, and the final product has a single Gaussian texture.