Atom-Probe Investigation of a Micro-Crack Associated with Hydrogen in a Fe-Ti Alloy

摘要

We have for the first time witnessed the formation of a micro-crack and its development into a fracture using field ion microscopy. The crack initiated at a grain boundary intersection and propagated mainly, though not entirely, along the grain boundary. Compositional analysis at a hydrogen-produced micro-crack in a Fe-0.29 wt % Ti alloy by the high-performance time-of-fight atom-probe showed a large amount of hydrogen at the crack (H and H sub 2 ) and iron-hydrides (FeH, FeH sub 2 ). In contrast, hydrogen in any form is rarely found in other surface areas, or in the bulk. (ERA citation 06:017080)