The effect of Tb on elastocaloric and mechanical properties of Ni-Mn-In-Tb alloys

The influence of partial substitution of Tb for In on the microstructure, martensitic transformation, mechanical properties, and elastocaloric effect of Ni50Mn34In16−xTbx (x = 0, 0.1, 0.3, 0.4, 0.5) alloys have been investigated. Single-phase alloys are obtained for x ≤ 0.3, and Tb-rich secondary phase precipitates distribute along the grain boundaries of the parent phase for x > 0.3. The phase transformation temperatures initially increase with increasing Tb addition, then decrease with more than 0.3 at.% Tb addition. The existence of secondary phase results in the grain refinement thus improves the mechanical properties of Ni-Mn-In-Tb alloys. A large adiabatic temperature change of 5.1 K induced by uniaxial stress application is observed in Ni50Mn34In15.6Tb0.4.