Abstract
From a direct observation of dislocation-obstacle interaction utilizing in situ straining experiments in transmission electron microscope (TEM), the obstacle strength factor could be evaluated from pinning angles of dislocation cusps. We simulated this process: we produced a dislocation cusp by molecular dynamics simulation of interaction between an edge dislocation and a void or a hard precipitate in copper, and calculated the TEM image by multislice method. In two-beam conditions, cusp images showed inside-outside contrast depending on the sign of the diffracting vector and other variations with the specimen geometry. The pinning angles measured on TEM images ranged up to a few tens of degrees and were between the true angles for the two partial dislocations. Characteristics and contrast mechanisms of cusp images were discussed based on those of dislocation dipoles.
Original language | English |
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Pages (from-to) | 413-417 |
Number of pages | 5 |
Journal | Materials Transactions |
Volume | 55 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2014 |
Keywords
- Dislocation-obstacle interaction
- Image simulation
- Irradiation hardening
- Transmission electron microscope
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering