Giant elastocaloric effect in a Mn-rich Ni44Mn46Sn10 directionally solidified alloy
Guoyao Zhang, Zongbin Li, Jiajing Yang, Bo Yang, Dunhui Wang, Yudong Zhang, Claude Esling, Long Hou, Xi Li, Xiang Zhao, Liang Zuo
Abstract
The superelastic and elastocaloric properties of a Mn-rich Ni44Mn46Sn10 polycrystalline alloy prepared by directional solidification were studied. Owing to the coarse columnar shaped grains with strong ⟨001⟩A preferred orientation, a large superelastic strain up to 8% and a transformation strain of 5.6% can be obtained through compressive stress induced martensitic transformation. Moreover, a giant adiabatic temperature variation up to –18 K was achieved on removing the stress. Such a remarkable elastocaloric effect is attributed to the large transformation entropy change through composition modification and the enhanced mechanical properties due to the formation of a highly textured microstructure in the directionally solidified alloy.