PNNL

Abstract

Recent results are presented demonstrating the application of cross-sectional analytical transmission electron microscopy (ATEM) to corrosion and cracking in high-temperature water environments. Microstructural, chemical and crystallographic characterizations of buried interfaces at near-atomic resolutions are shown to reveal evidence for unexpected local environments, corrosion reactions and material transformations. Information obtained by high-resolution imaging and analysis indicates the corrosion and deformation processes during crack advance and provides insights into the mechanisms controlling environmental degradation. Examples of intergranular attack and cracking in type 316 austenitic stainless steel and Ni-base alloy 600 are presented to illustrate the value of this approach.