Mechanisms of accommodation of deformation at grain boundaries in BCC materials
Two of the mechanisms of accommodation of deformation at grain boundaries in body-centered cubic material were studied using transmission electron microscopy and diffraction. These are: the absorption of dislocations in near-coincidence boundaries and the accommodation of a change in GB plane in a low angle boundary. The contribution of these mechanisms to the continuation of plastic flow, the accommodation of an intergranular crack, and deformation mechanisms at high temperatures such as grain boundary sliding and grain boundary migration is discussed. The O-lattice geometrical description of interfaces was used to model the structure of the grain boundaries. A program was developed for the routine calculation of grain boundary structure and for comparison with experimental observations. Lattice dislocations are shown to dissociate in near-coincidence boundaries into dislocations with Burgers vectors characteristic of a lattice associated with the coincidence site lattice.
- Research Organization:
- Lawrence Berkeley Lab., CA (USA)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 5323406
- Report Number(s):
- LBL-14613; ON: DE82018805
- Resource Relation:
- Other Information: Thesis
- Country of Publication:
- United States
- Language:
- English
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