In-Situ TEM Investigation of Interactions between Irradiation Defects and Crystal Defects in Austenitic Stainless Steels

Abstract

This paper presents our recent efforts that use in-situ irradiation TEM experiments as a tool to understand the interaction process of irradiation defects with crystal defects in austenitic stainless steels (ASS). Various irradiation defect clusters, such as dislocation loops, stacking fault tetrahedra, and voids, can form during the heavy-ion irradiation of ASS. [1] Once nucleated, they interact with the pre-existing crystal defects in the ASS, such as dislocations, grain boundaries and interfaces. These interactions may result in the annihilation of irradiation defects, and thus are important for designing the microstructure of materials with improved irradiation resistance. However, the fundamental mechanisms that control the interactions between irradiation defects and crystal defects are not well understood, due to the complexity of the interaction process. Time-resolved in-situ TEM experiments have the ability to offer real-time observation of the development of irradiation defects and their interactions with crystal defects. These in-situ TEM studies provide experimental evidences as the input to aid the development of physical models for the predication of the microstructure-property relationship of ASS in the nuclear reactor environment.