Evaluation of plasma sprayed sacrificial thermal barrier coatings for core catcher of future Sodium cooled Fast Reactors

Post exposure investigations indicated that YSZ coating was leached out completely, whereas alumina coating was intact with the substrate. At low pressure, alumina had shown weak interaction with sodium i.e., formation of sodium aluminate within a shallow depth. However, at slightly higher pressure, delamination of coating was observed. The results indicated that plasma sprayed alumina and YSZ coatings are not stable in present test configuration. Alternate methods for sacrificial lining as well as materials need to be explored.