Anomalies of the thermophysical properties near first-order phase transitions in experiments with periodic heating

The effect of the relaxation time and heat of a first-order phase transition on the magnitude of the phase delay of a temperature wave in a sample is analyzed on the basis of the solution of the heat-conduction equation. The results of measurements of the thermal diffusivity of titanium in the region of the temperatures of the $\alpha$–$\beta$ transition, which were performed at different frequencies of modulation of the heat flux, are presented. It is shown that the true values of the thermal diffusivity of titanium correspond to the values obtained at $225$ Hz. The relaxation time of the transition is determined from these data.