Effect of Annealing Process on Microstructure and Magnetic Properties of Fe-3.0 Wt Pct Si Non-oriented Silicon Steel Ultra-Thin Ribbons Prepared with Planer Flow Casting

Planar flow casting is a high-efficiency and energy-saving method to manufacture non-oriented silicon steel ultra-thin ribbons. In this study, we prepared Fe−3.0 wt pct Si non-oriented silicon steel ultra-thin ribbons with this process and investigated the effects of different annealing temperatures and durations on the microstructure and magnetic properties of the as-cast ribbons. The results show that the surface grain size gradually increases with elevated annealing temperature. However, the annealing duration has a relatively minor influence on grain growth, only a modest increase during 900 °C annealing. Meanwhile, the favorable {100} texture diminishes while the {110} and {111} texture intensifies with increasing annealing temperature and duration, leading to an overall gradual decline in magnetic induction owing to texture degradation. Notably, the iron loss undergoes a significant initial reduction due to the sharp decrease in dislocation density after annealing. Subsequently, as the annealing temperature and time increase, the iron loss gradually decreases, primarily because of the increase in grain size.