Stress-induced transformations at low temperatures in a Ni ₄₅Co₅Mn₃₆In₁₄ metamagnetic shape memory alloy

The martensitic transformation behavior in a Ni₄₅Co ₅Mn₃₆In₁₄ was investigated at low temperatures. Almost perfect superelasticity was confirmed below 200 K. The reverse transformation finishing stress monotonically decreased with decreasing temperature and the forward transformation starting stress changed from a decrease to an increase at ∼125 K. The temperature dependence of equilibrium stress had the same tendency as that of equilibrium magnetic field, allowing the thermal transformation arrest temperature to be determined. The temperature dependence of hysteresis in stress-induced transformation was also similar to that in magnetic-field-induced transformation, and the levels of dissipation energy yielded by the stress and magnetic field were intrinsically equivalent.