Preparation of Fe76Si9B10P5 Nanocrystalline Magnetic Cores by Direct-Nanocrystallizing Method during Spark-Plasma Sintering

Bulk nanocrystalline Fe76Si9B10P5 magnetic cores were sintered using spark-plasma technique through direct-nanocrystallizing method by Fe76Si9B10P5 amorphous alloy gas atomization powder. The saturated magnetic induction of magnetic cores was 1.5 T, and the maximum permeability was 1470. Coercive force was 38 A/m. X-ray analysis showed that the crystallization temperature of Fe76Si9B10P5 alloy decreased with the increase of the pulse current and sintering pressure. High resolution electron microscopic analysis results showed that the smaller nanograin size were obtained after spark-plasma sintering with the crystallization temperature decrease. In addition, the crystallization behaviour of the Fe76Si9B10P5 during sintering process was analyzed, and the influence of direct crystallization during spark-plasma sintering on the soft magnetic properties was discussed.