Large Glass-forming Ability and Magnetocaloric Effect in Gd₅₅Co₂₀Al₂₃Si₂Bulk Metallic Glass

In this study, we investigated the glass-forming ability (GFA) and magnetocaloric effect (MCE) of $Gd₅₅Co₂₀Al₂₃Si_2$ bulk glassy alloy. It is found that the addition of 2 at% Si is effective for extension of the supercooled liquid region (${\Delta}T_x$), the ${\Delta}T_x$ is 55 K for the $Gd₅₅Co₂₀Al₂₅$ glassy alloy, and increases to 79 K for the $Gd₅₅Co₂₀Al₂₃Si_2$ alloy. As a result, $Gd₅₅Co₂₀Al₂₃Si_2$ glassy alloys with diameters up to 5 mm were successfully synthesized. The alloys also exhibit large MCE, i.e., the magnetic entropy change (${\Delta}S_m$) of 8.9 J $kg^-1\;K^-1$, the full width at half maximum of the ${\Delta}S_m$ (${\delta}T_FWHM$) of 87 K, and the refrigerant capacity (RC) of 774 J $kg^-1$.