Effect of Co Doping on the Elastocaloric Effect of Ni-Mn-Ga-Co Alloy

Large latent heat is produced in the stress-induced martensitic phase transition process of Ni-Mn-Ca-based materials, i.e., elastocaloric effect. That makes such materials show tremendous potential for solid-state refrigeration which is identified as one of the most promising non-vapor-compression cooling devices. However, the still low refrigeration ability of these materials restricts further commercially promoting of solid-state refrigeration. In this work, we adjusted the Co content to regulate the elastocaloric effect for the Ni51.5Mn25Ga23Co0.5. According to the results, the transformation strain and ratio of loading stress/transformation temperature (ds/ dT) were increased by replacing the Ni atoms with a little more Co, leading to an improvement of the stressinduced transformation entropy-change.Ss. As a result, a huge.S s of 45.0 JKg(-1)K(-1) is achieved in Ni50Mn25Ga23Co1 alloy.