抄録
The 304/316 series of austenite stainless steels are used in light water reactors as structural materials. As a result of the high temperatures and neutron irradiation in reactor, dislocation defects will form in stainless steel, causing an increase in the hardness and a decrease in the ductility of the material. In this work, high purity 316L stainless steel model alloys with three different Si contents were ion irradiated at 290°C or 400°C to investigate the black dot and Frank loop formation mechanism influenced by Si addition. Black dot defect formation mainly occurs at 290°C. It is Frank loop in nature with its formation not affected by Si addition. Frank loop is the main defect at 400°C, and both loop density and the average size are substantially suppressed by Si addition. This may be caused by silicon’s role in enhancing effective vacancy diffusivity and thus promoting recombination. The trend of irradiation hardening measured verses temperature matches the microstructure observed.
