Specific Heat of Zr-2.5nb Pressure Tube Material Measured by Differential Scanning Calorimetry (DSC)

Abstract

Specific heats of Zr-2.5Nb pressure tube material have been measured by differential scanning calorimetry (DSC) between 100°C and 1200°C using a heating and cooling rate of 20°C/min. A hysteresis was observed in the specific heat curves between heating and cooling. A maximum value occurs at a higher temperature on heating than on cooling, and the magnitude is larger for cooling when compared to heating. The as-manufactured tube material showed a small enthalpy change during first heating, attributed to decomposition of meta-stable β-Zr; and this did not appear on second heating after being first heated to 1200°C. Further studies are suggested to characterize the hysteresis behaviour.