Giant elastocaloric effect induced by lower stress in Ni-Mn-In-Fe ferromagnetic shape memory alloys

Abstract

The influence of the substitution of Fe on the mechanical properties and elastocaloric effect (eCE) in Ni50Mn36−xIn14Fex (x = 0.5, 1, 1.5, 2, 4, 6) ferromagnetic shape memory alloys (FMSMAs) have been investigated. The results show that mechanical properties are improved by iron doping. The fracture stress and strain of arc melting Ni50Mn34In15Fe2 alloy are 411 MPa and 10.1 %, respectively. A large adiabatic temperature change (ΔTad) of up to 9.8 K was obtained via the reverse process of compressive stress-induced martensitic transformation with a lower driving stress of 175 MPa compared to the undoped alloy (256 MPa). These results show that this approach is a practical solution to the challenge of obtaining shape memory alloys with a large elastocaloric effect.