Effect of dy on structure and magnetic properties of CoPt alloys

Abstract

The effects of Dy on the microstructure and magnetic properties of Dy _xCo_50−xPt₅₀ alloys were investigated. The XRD results indicate that all the alloys homogenized at 1000 °C contain only a single A1 (fcc) phase, while the alloys annealed at 675 °C consist of a hard-magnetic face-centered-tetragonal (fct) phase and a magnetically soft face-centered-cube (fcc) phase. Maximum values for the coercivity H _c and remanence ratio m _r were achieved in Dy_0.4Co_49.6Pt₅₀ alloys annealed at 675 °C for 80 min. For the series of Dy _xCo_50−xPt₅₀ alloys annealed at 675 °C for 60 min, H _c decreases monotonically with increasing Dy concentration, but m _r is first enhanced and then weakened.

Keywords

magnetic properties / degree of ordering / Co-Pt alloys / crystal structure

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