Effect of Co/Ni Substituting Fe on Magnetocaloric Properties of Fe-Based Bulk Metallic Glasses

In this work, Fe_80-xM_xP₁₃C₇ (M = Co, Ni; x = 0, 5 and 10 at.%) bulk metallic glasses (BMGs) were prepared, and the effect of the Co/Ni elements substitution for Fe on the magnetocaloric properties of Fe₈₀P₁₃C₇ BMG has been investigated systematically. The Curie temperature (T_C) of the present Fe-based BMGs increases with the substitution of Fe by Co/Ni. The magnetic entropy change ($\Delta S_{\mathrm{M}}$) of the present Fe-based BMGs increases first and then decreases with the increase of Fe substituted by Co, but monotonically decreases with the increase of Fe substituted by Ni. Among the present Fe-based BMGs, the Fe₇₅Co₅P₁₃C₇ BMG exhibits the maximum $\Delta S_{\mathrm{M}}$ value of 5.21 J kg⁻¹ K⁻¹ at an applied field of 5 T, which is the largest value among Fe-based amorphous alloys without any rare earth elements reported so far. The present Fe-based BMGs exhibit the large glass forming ability, tunable T_C and enhanced $\Delta S_{\mathrm{M}}$ value, which are beneficial for magnetic refrigerant materials.