Compatibility of materials in fusion first wall and blanket structures cooled by liquid metals

Abstract

Compatibility studies of lithium and lead-lithium have been conducted over approximately the past ten years in support of fusion reactor applications. At the present time, there exists a fairly good understanding of the overall corrosion mechanisms in both liquid metals and of differences in corrosion behavior between the two environments, Pb17Li is more aggressive toward steels due to the higher solubilities of iron, nickel and chromium in this liquid metal. While nitrogen and carbon can have significant effects on corrosion of steels by lithium, particularly at 400–500°C, these elements have little influence in Pb17Li. The effects of these liquid metal environments on the mechanical properties of steels have been characterized and only minor problems are anticipated. The state of knowledge regarding the dependence of the corrosion rate of steels exposed to Pb17Li on blanket operating parameters is much more advanced than that for lithium. For both liquid metals, more in-depth studies of deposition and magnetic field effects are needed.