High magnetic performance ultra-thin Fe-6.5Si ribbons fabricated by planner flow casting and annealing

Abstract

Fe-6.5 wt.%Si steel is one of the most attractive soft magnetic materials for making iron cores with low noise and low power loss. The planner flow casting method was regarded as a promising method to obtain ultra-thin ribbons of Fe-6.5Si alloy. In this study, Fe-6.5Si ribbons with a thickness of 0.03 mm were prepared by planner flow casting. Samples were heat-treated at various temperatures. It is revealed that the grain size on the wheel surface and free surface gradually increases with increasing annealing temperature. The initial {100} fiber texture of the wheel and free surfaces is weakened after annealing, transforming to {001} 〈510〉 on the wheel surface and to {229} < 11 2 2 > on the free surface after annealing at 1150 °C for 1 h. The texture parameter and dislocation density are the key factors affecting the magnetic induction intensity, showing an inverse correlation with the texture parameter and dislocation density. Furthermore, the iron loss is mainly influenced by the grain size, with an optimal grain size of 10 μm. Considering the magnetic induction intensity and iron loss, the optimal annealing temperature is determined to be 1100 °C, resulting in a magnetic induction intensity of B8 = 1.26 T and B50 = 1.65 T, and iron loss values of P1/400 = 14.1 W/Kg and P0.2/5000 = 11.1 W/Kg.