Microstructural Evolution and Interfacial Stabilization Mechanisms of Mo‐Re Alloy Exposed to High‐Temperature Liquid Lead

The compatibility and interfacial corrosion behavior of the 86 wt%Mo‐14 wt% Re alloy were systematically investigated in liquid lead containing 10 −2 wt% dissolved oxygen at 600°C for up to 1000 h. Microstructural and phase analyses revealed a time‐dependent, multi‐stage oxidation process. The total scale thickness expanded from 55.38 μm at 400 h to 177.20 μm at 1000 h. The degradation follows a sequential phase‐transformative path: initial selective oxidation yields a transient MoO 2 layer, which subsequently reacts with the liquid lead and oxygen to form a stratified structure containing an outer block‐like Pb 2 MoO 5 phase and an intermediate columnar PbMoO 4 layer. This compact Re‐enriched inner barrier effectively minimizes further lead penetration and oxygen diffusion. The longer exposure time may lead to the stabilization of the corrosion products, which could play a critical role in protecting the Mo‐Re alloy from liquid lead erosion. These findings elucidate the self‐stabilizing potential of Mo‐Re alloys, providing a critical theoretical foundation for their application as structural components in next‐generation lead‐cooled fast reactors.