Effect of Vapor Deposition on the Interdiffusion Behavior between theMetallic Fuel and Clad Material

摘要

This study aimed to evaluate the performance of diffusion barriers in order to prevent fuel-cladding chemical interaction (FOCI) between the metallic fuels and the cladding materials, a potential hazard for nuclear fuel in sodium-cooled fast reactors. In order to prevent FCCI, Zr or V metal is deposited on the ferritic-martensitic stainless steel surface by physical vapor deposition with a thickness up to 5μm. The diffusion couple tests using uranium alloy (U-10Zr) and a rare earth metal such as Ce-La alloy and Nd were performed at temperatures between 660-800℃. Microstructural analysis using SEM was carried out over the coupled specimen. The results show that significant interdiffusion and an associated eutectic reaction ocurred in the specimen without a diffusion barrier. However, with the exception of the local dissolution of the Zr layer in the Ce-La alloy, the specimens deposited with Zr and V exhibited superior eutectic resistance to the uranium alloy and rare earth metal.