Giant elastocaloric effect covering a wide temperature region in a directionally solidified Ni50Mn30Ti20 alloy

Abstract

High-performance elastocaloric materials coupled with giant elastocaloric effect and broad working temperature range are highly demanded for solid-state refrigeration applications. Here, we demonstrate giant elastocaloric response covering a wide temperature region in a directionally solidified Ni50Mn30Ti20 alloy with the columnar-grained microstructure and <001>A preferred orientation. Owing to the effective reduction in the transformation temperatures (∼200 K) through composition tuning, large superelastic response with the recovery strain of 9% is obtained from 213 K to 333 K, giving rise to the maximum adiabatic temperature change as high as −31.3 K upon unloading. Moreover, giant |ΔTad| values higher than 20 K have been well achieved within a wide temperature window of 90 K ranging from 223 K to 313 K.