Investigation of the sensitivity to EAC of steel T91 in contact with liquid LBE

The ferritic-martensitic steel T91 is one of the most promising material for application in the generation IV type reactors. However, there are critical issues, such as the susceptibility to damage of the steel in contact with the heavy liquid metals and their effect on the mechanical properties of structural materials. In this context, it was initiated a study of the boundary conditions, necessary to ascertain the sensitivity of the T91 to environmentally assisted cracking when loaded in contact with the liquid lead-bismuth eutectic. A series of tensile tests were carried out in a cell where the specimens were immersed in static LBE. Results showed that at high temperature the steel in contact with the liquid metal had a slight decrease of yield and UTS value and a marked increase in the elongation to rupture. However, at low temperature the elongation to rupture and the reduction of area decreased, indicating the sensitivity to EAC.