A multielement alloying strategy to improve elastocaloric and mechanical properties in Ni–Mn-based alloys via copper and boron
Abstract
Ni–Mn-based shape memory alloy is a promising candidate as the solid-state elastocaloric refrigerant in the micro- or nano-refrigeration fields owing to the required small driving force. In this letter, we report a multielement alloying strategy, i.e., the co-substitution of non-magnetic element and boron for Mn, to improve the elastocaloric refrigeration efficiency and mechanical properties simultaneously. Under Cu and B co-substitution, a large adiabatic temperature change of –12.8 K and a giant specific adiabatic temperature change of 41.0 K/GPa were obtained in the directionally solidified Ni50(Mn31.7Cu2.5B0.3)In15.5 alloy. The proposed alloying manner is also favorable to enhance fracture resistance and cyclability.