Microstructure and Texture of Strip Cast Grain-Oriented Silicon Steel after Symmetrical and Asymmetrical Hot Rolling

Abstract

A grain-oriented silicon steel as-cast strip was produced by twin-roll strip casting. Then the as-cast strip was symmetrically and asymmetrically hot rolled, respectively. The microstructure and texture evolution was investigated by a combination of optical microscopy, X-ray diffraction, and electron backscattered diffraction methods. The microstructure of the as-cast strip consisted of ferrite matrix and martensite, and the texture was characterized by pronounced {001} 〈0vw〉 fiber texture in the outer layers and nearly random texture in the inner layers. After symmetric hot rolling, the microstructure was composed of deformed ferrite grains, proeutectoid ferrite grains and pearlite. The texture was characterized by pronounced {001} 〈0vw〉 fiber texture in the outer layers and mild γ-fiber texture in the inner layers. By contrast, when asymmetric hot rolling was applied, considerably dispersive proeutectoid ferrite and pearlite and relatively strong Goss texture were observed, together with strong {001} 〈0vw〉 fiber texture in the outer layers.