Glass-Forming Ability and Magnetocaloric Effect in ${rm Gd}_{55}{rm Co}_{20}{rm Al}_{25-{rm x}}{rm Si}_{rm x}$ Bulk Metallic Glass

摘要

In this letter, we investigated the effect of Si addition on glass forming ability and magnetocaloric effect in Gd-Co-Al bulk glassy alloys. It is found that the addition of only 1 at.% or 2 at.% Si is effective for extension of the supercooled liquid region $(Delta T_{x})$ and decrease of the fragility parameter $m$. As a result, Gd-based glassy alloys with diameters up to 5 mm were successfully synthesized. The alloys also exhibit large MCE, i.e., having the magnetic entropy change $(-Delta S_{rm m})$ of 9.2 ${rm J} {rm kg}^{-1} {rm K}^{-1}$ , the full width at half maximum of the $-Delta S_{rm m}$ $(delta T_{rm FWHM})$ of 87 K, and the refrigerant capacity (RC) of 800 ${rm J} {rm kg}^{-1}$.