Corrosion-erosion and mass transfer dynamic behaviors of reduced activation ferritic/martensitic steel in a nonisothermal Pb-17Li system

摘要

Corrosion tests were performed to study corrosion–erosion behaviors of reduced activation ferritic/martensitic steel JLF-1 and mass transfer behaviors of metal elements in a nonisothermal Pb-17Li flow. The tests were performed using isothermal and nonisothermal mixing pots at approximately 773 K for up to 1000 h. The test results indicate that the steel surface corroded according to the dissolution of steel compositions (i.e., Fe and Cr) in the flowing Pb-17Li. The corroded surface then revealed a granular structure with small pebble-shaped protrusions. The protrusions were formed by preferential corrosion along the boundaries of microstructures on the steel surface. Small-scale corrosion-erosion was caused by the removal of the small protrusions from the steel surface in flowing Pb-17Li. There was also large-scale corrosion–erosion according to the destruction of the steel surface after the surface was deeply corroded. Metal elements, such as Fe, Cr and Ni, were dissolved from the steel in the flowing Pb-17Li. They were transferred to a low-temperature region with the Pb-17Li flow and finally precipitated as round-shaped particles on metal wires installed in the low-temperature region of the mixing pot.