3% Si 무방향성 전기강판의 철손에 미치는 Y 첨가와 열연판 소둔 온도의 영향

Abstract

Research on improving core loss of 3% Si non-oriented electrical steels was conducted by Y addition and changes of hot band annealing temperature. Clear effects on facilitating grain growth and lowering core loss were observed with addition of 0.016% of Y. Grain size was reduced and core loss increased in case of Y free steels and steels with more than 0.016% Y. It is assumed that hysteresis loss of 0.029% Y steels is lowered by facilitating grain growth. Low hot band annealing temperature (950℃, 1000℃) showed lower core loss compared to high hot band annealing temperature (1050℃, 1100℃, 1150℃) in 0.016% Y added steels. Low hot band annealing temperature has advantage in controling process. Therefore, it is assumed that low Y steel can have advantage on improving core loss in terms of loe hot band annealing temperature processing condition. By results of AES analysis of Y added specimens, Y was not segregated. Instead, Y was located within grain in form of 1 ∼ 10 μm diameter Y nitrides and Y sulfides. MnS was not observed. On the contrary, AlN and MnS were observed in Y free specimen. Thus, adding small amount of Y is assumed to inhibit formation of micro sulfides(e.g. MnS) which suppress grain growth and deteriorate magnetic property of electrical steels.