Radiation-induced segregation in austenitic stainless steel type 304: Effect of high fraction of twin boundaries

Abstract

The effect of high fraction of twin boundaries on radiation-induced segregation (RIS) in type 304 stainless steel (SS) was investigated using 4.8 MeV proton beam at 300 degrees C. Type 304 SS samples were irradiated to 0.86 and 1.00 displacement per atom (dpa) and characterization of RIS was done using Electrochemical Potentiokinetic Reactivation (EPR) tests at different iepth from the surface. Localized attack on different microstructural features, grain and twin boundaries and in-grain pit-like features, was further evaluated by atomic force microscopy. The results clearly indicated that attack was mostly confined to twin boundaries, implying that the twin boundaries acted as a preferred defect sink. (C) 2011 Elsevier B.V. All rights reserved.