Analysis of strain distribution of lead–bismuth eutectic inside a stainless steel cup by wavelength-resolved neutron imaging

• Crystal structure of lead–bismuth eutectic alloy was investigated using neutron diffraction and Rietveld analysis. Gradual changes in the crystal structure with aging were observed. • Deformation of lead–bismuth eutectic alloy inside a cup was measured using wavelength-resolved neutron imaging method. Lead-bismuth eutectic has emerged as a promising candidate for liquid metal coolant for Gen-IV nuclear reactors. Lead-bismuth eutectic is a unique material that expands gradually within the solid state. It may induce pipe deformation or rupture if it solidifies in a pipe or a container. In this study, the strain distributions of lead–bismuth eutectic in stainless-steel cups were evaluated using wavelength-resolved neutron imaging method. The wettability-improved case exhibited significantly larger compressive strain than in the others. The adhesion between lead–bismuth eutectic and the inner surface of the cup was a critical issue in the present study.