Room temperature elastocaloric effect in polycrystalline Ni51Mn34In8Sn7 alloy

Room temperature elastocaloric effect as well as the effects of strain rate and loading stress have been studied in polycrystalline Ni51Mn34In8Sn7. The increase of strain rate reduces plastic deformation and lattice invariant strain, thus improving the superelasticity. Higher strain rate and stress facilitate the stress-induced structural transition and adiabatic environment, and so the temperature change (Delta T) increases at a rate of 1.77 K (1% s (1))(-1) and 1.78 K (10(2) MPa)(-1). A large Delta T of 4.2 K is obtained by optimizing the strain rate and loading stress, which is comparable to or even larger than those of many NiMn-based alloys at room temperature. This result suggests polycrystalline Ni51Mn34In8Sn7 as a desirable material for room temperature elastocaloric refrigeration. (C) 2019 Elsevier B.V. All rights reserved.