Development of anti-corrosion coating on low activation materials against fluoridation and oxidation in Flibe blanket environment

Abstract W coating by vacuum plasma spray process and Cr coating by chromizing process were performed on fusion low activation materials, JLF-1 ferritic steel and NIFS-HEAT-2 vanadium alloy. The present study discusses feasibility of the coatings as anti-corrosioncoating against fluoridation in Flibefor fusion low activation materials. Coatings were characterized by microstructural analysis and examination on chemical stabilityby corrosion tests. The corrosion tests were conducted with H 2 O–47% HF solution at RT and He–1% HF–0.06 H 2 O gas mixture at 823 K to simulate fluoridation and oxidation in Flibe. The coatings presented suppression of fluoride formation compared with JLF-1 or NIFS-HEAT-2, however weight loss due to WF 6 formation was induced, and much Cr 2 O 3 was formed.