Thermophysical properties of $\sigma$ phase in the $\rm Ni$–$\rm V$ system at high temperatures

Measurements of the thermal diffusivity and resistivity and an estimate of the thermal conductivity of $\rm Ni$–$62$ at $\%\,\rm V$ alloy are presented. It is found that a distinct temperature hysteresis of these properties associated with the mutual transformation of the high- and low-temperature forms of the $\sigma$ phase is observed in the heating–cooling cycles. This hysteresis is interpreted from the point of view of the formation of the alloy microcrystalline structure. It is established from the anomaly in the temperature dependence that a phase transformation occurs within the temperature interval of $1100$–$1180$ K and it is identified as an order–disorder transition.