Mass spectrometric studies on U-Pu-Zr alloy

Vaporisation studies on U-19 wt%Pu-6wt%Zr alloy were carried out by using a high temperature mass spectrometry. Pu(g) was the vapour species observed over the alloy. The pressure - temperature relations were derived over (solid + liquid) two phase and liquid phase regions in the temperature ranges 1481-1623 K and 1661-1773 K, respectively. The corresponding vapour pressure equations were found to be as log(ppu/Pa) = (−22254 ± 282)/T+(10.80 ± 0.18) and log(ppu/Pa) = (−22021 ± 1169)/T+(10.52 ± 0.68) respectively. The enthalpies of vaporisation of Pu(g) over these phase regions were deduced. The vapour pressure of Pu(g) over the U-Pu-Zr alloy and its enthalpy of vaporisation data have been obtained for the first time. The data obtained were compared with those obtained by computations based on experimental data on U-Zr and Pu-Zr binaries and ideal solution model.