Auger electron spectroscopy study of alloy 718 and 304L stainless steel irradiated with 800 MeV protons

It is well known that radiation produces changes in materials microstructure such as formation of defects, dissolution and redistribution of secondary phases, precipitation of new phases, etc. and changes in the grain boundary microchemistry by a process known as radiation-induced segregation (RIS). This paper describes the grain boundary microchemical characterization of alloy 718 and 304L stainless steel irradiated with hi.-h-energy protons at Los Alamos Neutron Science Center (LANSCE), performed by means of Auger electron spectroscopy (AES). In addition, nonirradiated alloy 718 was characterized as reference. The Auger results showed that as a consequence of exposure to proton radiation, the changes observed in alloy 718 were the disappearance of the nickel and niobium rich grain boundaries precipitates and RIS of the major alloying elements (nickel to grain boundaries, and chromium and iron away from grain boundaries). On the other hand, in irradiated AISI 304L no differences were observed between intergranular and transgranular areas. (C) 2001 Elsevier Science B.V. All rights reserved.