Corrosion Behavior of Materials Selected for FMIT Lithium System

The corrosion behavior of selected materials in a liquid lithium environment was studied in support of system-and component designs for the Fusion Materials Irradiation Test (FMIT) Facility. Testing conditions ranged from ∼ 3700 to ∼ 6500 hours of exposure to flowing lithium at temperatures from 230° to 270°C and static lithium at temperatures from 200° to 500°C. Principal areas of investigation included lithium corrosion/erosion effects on FMIT lithium system baseline and candidate materials. Material coupons and full-size prototypic components were evaluated to determine corrosion rates, fatigue crack growth rates, structural compatibility, and component acceptability for the lithium system. Based on the results of these studies, concerns regarding system materials and component designs were satisfactorily resolved to support a 20-year design life requirement for the FMIT lithium system.