The dislocation pattern at the tip of a non-propagating fatigue crack in an Fe-25Cr-1N steel (mass%) was characterized by electron channeling contrast imaging. Planar dislocation arrays on two different slip planes were observed at the crack tip. Each planar dislocation array acts as a barrier to the motion of the other planar dislocations on different slip planes, contributing to the enhancement of the resistance to the crack propagation. This paper employs ‘electron-channeling-contrast-imaging (ECCI) in scanning electron microscope’ technique to visualize fatigue crack tip dislocations in high nitrogen steel, and it showed highly planar dislocations interacting with pre-existing dislocations assisting non-propagating fatigue crack.
- Crack tip dislocation
- Electron channeling contrast imaging
- High nitrogen steel
- Non-propagating fatigue crack
- Planar dislocation array
ASJC Scopus subject areas
- Materials Science(all)