Magnetic Properties of Cast (Pr, Dy)-(Fe, Co)-(B, C) Alloys

Abstract

This experiment was carried out to investigate the effects of composition and annealing condition on the magnetic properties of the isotropic cast (Pr, Dy)-(Fe, Co)-(B, C) alloys. Compositions were Pr₁₅Fe₇₇B₈, Pr₁₅(Fe_0.9Co_0.l)₇₇(B_1-xC_x)₈ and (Pr_0.95Dy_0.05)₁₅(Fe_0.9Co_0.1)₇₇( B_0.5C_0.5)₈. In Pr₁₅(Fe_0.9Co_0.1)₇₇(B_1-xC_x)₈ alloys, the value of H_CJ increased with the increase of C substitution for B from x=0 to x=0.5. In these cast alloys, (Pr_0.95Dy_0.05)₁₅(Fe_0.9Co_0.1)₇₇(B_0.5C_0.5)₈ alloy after annealing 5 h at 800°C showed the best magnetic properties, (BH)_max=38.4 kJ/m³, H_CJ=392 kA/m, H_CB=248 kA/m and B_r=0.54T. From EDX analysis, it was known that this alloy consisted of two phases, (Pr, Dy)-rich phase and (Pr, Dy)₂(Fe, Co)₁₄(B, C) phase.