PNNL

Abstract

Oxide dispersion strengthened (ODS) steels are a prime candidate for high temperature, high dose cladding in advanced nuclear reactors. A 9Cr-ODS alloy was irradiated with 5 MeV Ni ions at temperatures of 500, 600 and 700ºC to doses up to 150 dpa. There was no significant change in the dislocation arrangement. For oxide particles, there is a small shrinkage in size and increase in density with increasing irradiation dose. The atom probe analysis on the unirradiated and the Ni ion irradiated 9Cr-ODS at 700ºC to 150 dpa shows similar spatial configuration of oxide particles. Radiation-induced void swelling was not identified following Ni ion irradiation. Irradiation with 1.0 MeV Kr ions at temperatures of 500, 600, 700 and 800ºC to doses of 30-50 dpa reveals the presence of voids in all the irradiation conditions and it is believed to be due to Kr ions trapped in the materials. This work confirms that oxide particles and the microstructure of the 9Cr- ODS show minimal and acceptable changes under irradiation at temperature up to 700ºC and doses up to 150 dpa.