On the Potential Synergies of Helium and Hydrogen on the Nucleation and Stability of Cavity Clusters in Inconel X-750® Irradiated in a High Thermal Neutron Flux Spectra

摘要

The degradation of structural materials as a result ofhelium and hydrogen generated through nucleartransmutation is now well documented; however, not fullyunderstood. The amount of these elements produced canbe accurately estimated if the neutron energy spectrum inthe irradiation environment is well known. Ourexperimental measurements have confirmed the fullretention of helium, and up to approximately 40% of thehydrogen produced by transmutation. Atomistic modelingsuggest that bubbles formed during irradiation have a highdensity helium core, surrounded by a hydrogen-enrichedmetal matrix interface. High resolution electron energyloss spectroscopy has been performed and supports theatomistic modeling conclusions by illustrating thehydrogen signal as a halo surrounding helium bubbles.Material has been characterized with doses up to 80 dpawith up to 25000 appm retained helium and ~2000 appmretained hydrogen. This paper will use these experimentalresults to gain an improved understanding of the effects ofirradiation on the structural integrity of austeniticmaterials following irradiation in a high thermal neutronflux spectra.