Cp measurements around the martensitic transformation temperature of a CuAlNi alloy

Cp measurements on a CuAlNi single crystal around its martensitic transformation temperature are made by differential calorimetry (DSC). The results show that the transformation is not finished at the general values of Mf (the finishing temperature of the parent phase → parent phase transformation during heating). The specific heat difference between the martensite and parent phase (ΔCp) is not equal to zero in the transformation temperature range. The critical stress inducing the martensite transformation is approximately a linear function of temperature. However, the ΔS value obtained by the use of a Clausius-Clapeyron-like relationship is a little larger than that measured by DSC.