SiC Coating by RF Sputtering as Tritium Permeation Barrier for Fusion Blanket

SiC coating is formed on the reduced activation martensitic steel JLF-1 by radio frequency sputtering. The coating thickness decreases with increased deposition temperature and increases with increased deposition time. The atomic ratio of Si and C nears 1:1 in coating, while oxygen fraction exists. The coating shows a trend that the crystallization starts from deposition temperature of 723 K, though the coating is amorphous. In this study, the deuterium permeation flux of bare JLF-1 is lower about two orders of magnitude than that of Eurofer97, which is thought as a reason of oxidation of bare JLF-1 during test. The deuterium permeation flux of coated JLF-1 is about one to two orders of magnitude lower than that of bare JLF-1.