High temperature chromium volatilization from Cr2O3 powder and Cr2O3-doped UO2 pellets in reducing atmospheres

► Chromium volatilization from Cr2O3 powder and chromia-doped UO2 pellets. ► Cr2O3 decomposition in metallic gaseous chromium and oxygen. ► Appearance of a CrO(l) liquid phase enhancing the doped-UO2 sintering process. ► Competition between the volatilization of Cr and sintering kinetics of UO2. ► Distinct volatilization phenomena before and after the porosity closure in the UO2.