CORROSION OF FERROUS-ALLOYS IN A FLOWING LITHIUM ENVIRONMENT

Liquid lithium has long been considered an attractive blanket material for fusion reactors because of its acceptable tritium-breeding and efficient heat-transfer characteristics. Corrosion data on weight loss and internal penetration are presented for ferritic and austenitic stainless steels exposed for up to 6500 h at 700 and 755 K in a forced-circulation lithium loop. The results indicate that the dissolution rates for austenitic steels approach a steady-state value after an initial period (approx. 1500 h) of much higher rates. The weight losses for ferritic steels follow a linear increase with time. The austenitic steels develop a porous ferrite layer after exposure to lithium. Measurements of the thickness of the ferrite layer follow the trends indicated by the weight loss data.