Enhanced Properties of CrAl Coated ATF Cladding

초록

After the Fukushima accident, studies on accident tolerant fuel cladding focusing to prevent hydrogen explosions have been actively performed. Manyresearchers have been working on modifications of commercial cladding, especially direct coating on the cladding surface. In this work, a CrAlbinary alloy system and an arc ion plating method were selected to grow a film on commercial Zircaloy-4 claddings. CrAl coating layers were systematically deposited on the cladding surface under various voltage conditions using targets manufactured in different ways. Microstructural characterizations and the evaluations of the mechanical properties showed that a robust coating layercan be achieved by controlling the deposition parameters. Surface roughness values satisfying required manufacturing criteria were achieved and wear resistance values of coated claddings also notably improved. Moreover, CrAlexhibits superior corrosion resitstance. These results suggest that CrAl films on Zircaloy-4 cladding are promising candidates for future ATF cladding.