Influence of the Pb–Bi hydrodynamics on the corrosion of T91 martensitic steel and pure iron

The Pb–Bi eutectic liquid alloy is considered as spallation target material in hybrid systems due to its suitable nuclear and physical properties. One of the parameters which may have a significant influence on the corrosion of steels in contact with molten lead alloys is the hydrodynamic regime. Corrosion tests have been performed in the CICLAD device at 400 and 470 °C at low oxygen concentrations and for various cylinder rotating speeds with T91 martensitic steel. The results obtained show that increasing the rotating speed leads to an increase of the corrosion rate. Moreover, the need for controlling finely the Pb–Bi physico-chemistry as well as the surface state of the samples is also shown by these tests. Finally, a comparison is made between the experimental corrosion rates and calculated values obtained by using equations expressing the mass transfer coefficient.