Preparation of Fe–Pt–Si Amorphous Ribbons and Their Coercivity after Crystallization

Abstract

Fe_xPt_ySi_z (x=60–90, y=10–70, z=10–40) ribbons were prepared using a melt-spinning technique. Fully amorphous ribbons were obtained for alloys containing approximately 20–30 at%Si. Crystallization of the amorphous ribbons yielded composite structures of L1₀ FePt and Pt–Si intermetallic compounds for Fe₄₅Pt₃₅Si₂₀ and Fe₄₇Pt₂₈Si₂₅. Fe₄₅Pt₃₅Si₂₀ amorphous ribbons were annealed at 700 K for 180 min, producing a grain size of approximately 40 nm in diameter, and a maximum coercivity of 160 kA/m.