Giant enhancement of the magnetocaloric response in Ni-Co-Mn-Ti by rapid solidification

Magnetocaloric refrigeration is a solid-state cooling approach that promises high energy efficiency and low environmental impact. It remains uncompetitive with conventional vapor-compression technologies due to lack of high-performing materials that exhibit large magnetocaloric effects in low magnetic fields. Here we report a game-changing enhancement of the magnetocaloric response in a transition-metal based Ni-Co-Mn-Ti. Mechanically and chemically stable rapidly solidified ribbons exhibit magnetic entropy changes as high as similar to 27 j.kg(-1)K(-1) for a moderate field change of 2 T, comparable to or larger than the best known materials for near -room temperature applications. The ribbons can be easily manufactured in large quantities and the transition temperature can be adjusted by varying Co concentration. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.