Flow rate dependent corrosion behavior of Eurofer steel in Pb-15.7Li

In future blanket concepts Eurofer, is foreseen as structural material which is in direct contact with flowing Pb-15.7Li at temperatures up to 550 deg. C. In earlier compatibility tests the corrosion behavior was studied at high flow velocities of ca. 22 cm/s in PICOLO loop and a large data base for RAFM steels was created. Dramatically high steel dissolution occurs near 400 μm/year. Meanwhile, development of modeling tools was integrated to describe the corrosion/precipitation processes and to extrapolate towards DEMO conditions. However, to perform reliable extrapolation, testing at smaller flow rates towards laminar flow is absolutely necessary. Samples exposed up to 3000 h at reduced 10 cm/s flow velocity showed a dissolution attack of about 300 μm/year. The simulation of the corrosion behavior at 10 cm/s by MATLIM code and the evaluated corrosion data are consistent and fit to our results obtained earlier at 480 and 550 deg. C at 22 cm/s campaigns.