Secondary recrystallisation behaviours of grain-orientated silicon steel produced by TSCR process

Abstract

Grain-oriented electrical steel is mainly used as the core material in electrical transformers, and its magnetic properties are closely related to the sharpness of Goss texture formed by secondary recrystallisation during high-temperature annealing. However, the mechanisms of abnormal Goss grain growth are still disputed in the literature. In this paper, grain-oriented silicon steel strips with AlN as main inhibitor were produced by thin slab casting and rolling process, and the evolution of microstructure and texture during high-temperature annealing was investigated. Moreover, the mechanisms of secondary recrystallisation were further discussed. The results show that secondary recrystallisation is actually a multi-stage process, and different mechanisms are at work at different stages. Coincident site lattice grain boundaries play an important role at the early stage of secondary recrystallisation, however, the role of high-energy grain boundaries and solid-state wetting should be more important at the later stage of secondary recrystallisation.