Influence of temperature on the microstructural evolution of SIMP and T91 steels in liquid lead-bismuth eutectic: Experiments and molecular dynamics simulations

The microstructural evolution of ferritic/martensitic steels SIMP and T91 in oxygen-saturated liquid LBE at different temperatures (400, 470, 550 and 620 °C) has been studied by experiments and molecular dynamics simulations. It is shown that the SIMP steel offers better oxidation resistance at 400–550 °C due to the formation of protective SiO2 particles and bands. At 620 °C, both the SIMP and T91 steels undergo dissolution corrosion with similar dissolved layer thicknesses. Molecular dynamics simulations reveal that the number of Fe-O pairs decreases with increasing temperatures and the enhanced dissolution of Fe makes the surfaces of the steel difficult to oxidize at 620 °C.