Deformation microstructures in ion-irradiated stainless steel

Although radiation damage in stainless steel has been studied extensively, the primary focus has been on microstructural development and welling in alloys irradiated to high dose and elevated temperatures. Considerably less effort has been directed to stainless steel irradiated to low doses at low temperatures. In particular, deformation of stainless steel, irradiated to low dose levels (<10 dpa) at lower temperatures (<300 C), has received relatively little attention. Earlier work has shown that the microstructure of stainless steel, neutron irradiated at temperatures <300 C, is comprised of a high density of small dislocation loops. Deformation bands were observed in material deformed at ambient temperature but no analysis of the bands was made. As part of a larger program to understand the underlying causes for irradiation assisted, stress-corrosion cracking (IASCC), the deformation of irradiated stainless steel is being evaluated. In this study, ion irradiation is used to simulate the microstructure expected after neutron irradiation to dose levels ≤ 10 dpa at temperatures near 300 C