A comparative study of the corrosion resistance of an austenitic steel in lithium and the eutectic lead-lithium alloy

In a number of designs of thermonuclear reactors, besides liquid lithium, the use of lead-lithium alloy of the eutectic composition (Pb/sub 83/ Li/sub 17/) is envisaged for tritium breeding, heat transfer, and protecting the primary wall. The interaction of this alloy with water and air is less vigorous as compared to lithium, and the (n, 2n) type reactions involving lead atoms can ensure a tritium-breeding factor exceeding unity in the blanket at a relatively low concentration of lithium in the alloy. Tests are carried out on the 18-10 steel in convective currents of lithium and the Pb-17Li alloy in order to compare their corrosive action on the austenitic chromiumnickel steels that are promising materials for the primary wall and the blanket. Based on the obtained results, the high corrosive activity of the lead-lithium alloy as compared to pure lithium can be explained in the following way: the increased solubility of iron in lead as compared to that in lithium alone cannot ensure the observed rate of mass transfer of the steel by the lead base alloy.