Corrosion and radiation response of advanced ferritic-martensitic steels for Generation IV application

For many Generation IV systems, ferritic-martensitic steels are considered candidates for core internals, cladding, or pressure vessels. The radiation response to proton and heavy ion irradiation and the corrosion response in supercritical water and lead-bismuth eutectic of two advanced steels, specifically HCM12A (Grade 122) and a 9Cr Oxide Dispersion Strengthened (ODS) steel are reported in this work. The HCM12A appears to harden in a similar manner to T91. In the 9Cr ODS alloy, the oxides particles shrink slightly under high heavy ion irradiation, but this loss in size is accompanied by an increase in density such that any loss of hardening appears to be negligible. When exposed to SCW, the 9Cr ODs alloy has a thinner and less porous oxide than HCM12A. Although the inner oxide layers of HCM12A exposed in SCW and LBE have some similarity, the outer magnetite layer has smaller and equiaxed grains when exposed to LBE as opposed to the large columnar grains when exposed in SCW. (author)