Effects of different Pu or Am contents on structure,energy and mechanical properties of uranium-based mixed oxides
The Pu or Am content in U-Pu and U-Am mixed oxides is crucial for the efficient recycling of nu-clear reactor fuel.The effects of different Pu or Am contents in uranium-based mixed oxides on their structures,mechanical properties and energies can help to understand and predict the behavior of fuel in boost reactors and the chemical or mechanical interactions with the cladding.Therefore,in this work,the DFT+U method based on density functional theory is used to explore the relationships between the structure and energy of UO2,PuO2 and AmO2 with U,and then study the effect of different Pu or Am contents in the UO2 structure on its structure,mechanical properties and energy.The results show that the incorporation of Pu or Am into the UO2 structure re-duces the lattice parameters,and both are between UO2 and PuO2 or AmO2.From the energy point of view,the different contents of Pu or Am into UO2 structure makes the variation trend of the formation energy of the system significantly different with the amount of doping.The formation energy of the U-Pu mixed oxide system is the low-est when the UO2 structure is doped with 25％Pu,while the U-Am mixed oxide system has the lowest formation energy when the UO2 structure is doped with 75％Am.In addition,we also discussed and analyzed the variation and difference of elastic parameters with different Pu or Am contents incorporated into the UO2 structure.
(U,Pu)O2(U,Am)O2StructureElasticityDensity functional theory
万方数据
维普
