Large magnetocaloric effect in low-cobalt-content Gd-Co-Al metallic glasses

Magnetic refrigeration represents a promising refrigeration technology. A number of Gd-based metallic glasses have been demonstrated to exhibit excellent magnetocaloric effect (MCE) and superior refrigerant capacity. The development of such metallic glasses often involves the identification of glass-forming alloys, in which the MCE is further evaluated. The process is laborious and time-consuming as it typically relies on conventional trial-and-error methods. In this work, we demonstrate the rapid identification of Gd-Co-Al alloys exhibiting excellent MCE. Specifically, we apply combinatorial synthesis paired with high-throughput characterizations to reveal the glass-forming range and obtain a guideline from existing literature. This substantially reduces the compositional space in which the MCE needs to be individually measured. Three new alloys, Gd 60 Co 10 Al 30 , Gd 65 Co 10 Al 25 , and Gd 70 Co 5 Al 25 , were found to have the highest refrigerant capacity within the Gd-Co-Al system. With the new alloys, it was further found that there exists a critical Co concentration and a critical Gd/Co ratio at which the refrigerant capacity approaches saturation within the Gd-Co-Al alloy system. These findings bear importance for the development of potential magnetic materials with larger refrigerant capacity.