Excluding molten fluoride salt from nuclear graphite by SiC/glassy carbon composite coating

다국어 초록 (Multilingual Abstract)

SiC coating and SiC/glassy carbon composite coating were prepared on IG-110 nuclear graphite (ToyoTanso Co., Ltd., Japan) to strengthen its inertness to molten fluoride salt used in molten salt reactor(MSR). Two kinds of modified graphite were obtained and correspondingly named as IG-110-1 and IG-110-2, which referred to modified IG-110 with a single SiC coating and a SiC/glassy carbon compositecoating, respectively. Both structure and property of modified graphite were carefully researched andcontrasted with virgin IG-110. Results indicated that modified graphite presented better comprehensiveproperties such as more compact structure and higher resistance to molten salt infiltration. With theprotection of coatings, the infiltration amounts of fluoride salt into modified graphite were much lessthan that into virgin IG-110 at the same circumstance. Especially, the infiltration amount of fluoride saltinto IG-110-2 under 5 atm was merely 0.26 wt%, which was much less than that into virgin IG-110 under1.5 atm (13.5 wt%) and the critical index proposed for nuclear graphite used in MSR (0.5 wt%). The SiC/glassy carbon composite coating gave rise to highest resistance to molten salt infiltration into IG-110-2,and thus demonstrated it could be a promising protective coating for nuclear graphite used in MSR.

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