PNNL

Abstract

Irradiated austenitic stainless steels removed from Russian water-cooled VVERs experience irradiation temperatures and He/dpa conditions that are very similar to steels to be used in ITER. Data are presented on the radiation hardening of the Russian analog of AISI 321 at 0.2 to 15 dpa in the range of 285 to 320??. The Russian variant of the ring-pull tensile test was used to obtain mechanical prop-erty data. Microhardness tests on the ring specimens provide useful information throughout the deformed regions, but at high hardening levels caution must be exercised before application of a widely accepted hardness-yield stress correla-tion to prediction of tensile properties. Low-nickel austenitic steels are very prone to form deformation martensite, a phase that increases strongly with the larger deformation levels characteristic of microhardness tests, especially when compared to the 0.2% deformation used to define yield stress.