Results 221 to 230 of about 16,888 (264)

Energy of Polygonal and Elliptical Dislocation Loops

physica status solidi (b), 1966
AbstractA general expression for the elastic strain energy of an arbitrary N‐sided planar polygonal dislocation loop is obtained from the stress field of dislocation segments using isotropic elasticity. This expression can be used to approximate the energy of any curved dislocation loop to any degree of accuracy.
G. C. T. Liu, J. C. M. Li
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On the Determination of the Nature of Dislocation Loops

Philosophical Magazine, 1964
Abstract A simplication of the electron microscope method for determination of the nature of dislocation loops is described. Full determination of the relevant diffraction conditions and of the Burgers vectors of the loops are avoided and knowledge of the sense of inclination of the loops and of the rotations of image and diffraction pattern is not ...
B. Edmondson, G. K. Williamson
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Dislocation Loops in a‐Silicon Nitride

Journal of the American Ceramic Society, 1993
Thin foils of fully dense, but only partially transformed, hot pressed silicon nitride materials have been examined by high‐resolution transmisson electron microscopy. Large untransformed grains are seen to contain high densities of nanometer dimension, round or oval, textural features. Examination at high magnification shows thest
Chong‐Min Wang, Frank L. Riley, Francisco Castro, Iñigo Iturriza   +3 more
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Energy of dislocation loops in crystals

physica status solidi (a), 1986
Methods of calculating the energy of dislocation loops of arbitrary type and size as well as their interaction are proposed in a model of the solid state as a non-localized quasi-continuum. Also the model of a Gauss distribution of the dislocation density for a single dislocation is considered.
A. F. Vladimirov, E. N. Moos
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Analysis of Dislocation Loops in Superlattices

physica status solidi (b), 1967
AbstractA detailed computer analysis of dislocation loop behavior in DO3 and B2 type superlattices has been performed. This analysis shows that DO3 superlattice dislocation nucleation most probably proceeds by the independent nucleation of four 1/2 a0 〈111〉 loops while the same process in B2 superlattices occurs by the independent nucleation of two ...
M. J. Marcinkowski, H. J. Leamy
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Dechanneling due to dislocation loops

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1988
Abstract A theoretical description of axial dechanneling due to a special type of dislocation loops is presented. It is based on the discontinuous model with the displacement field calculated using the theory of Burgers. Using RBS data of Bentini et al. (1987) buried layers of dislocation loops in silicon are analysed.
Konrad Gärtner, Amaldo Uguzzoni
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The long-range forces between dislocation loops and dislocations

The Philosophical Magazine: A Journal of Theoretical Experimental and Applied Physics, 1964
The long-range elastic interactions between dislocations and loops, both prismatic and shear, have been calculated for an isotropic medium.
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Analysis of passing dislocation loops

Physica Status Solidi (a), 1974
The equilibrium configurations of passing dislocation loops on parallel slip planes have been determined as a function of applied stress using numerical techniques. It is shown that the stable equilibrium configurations of the loops correspond to minima in the energy surface determined by two loop radii, while the unstable equilibrium configurations ...
K. Sadananda, M. J. Marcinkowski
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The climb of dislocation loops in zinc

Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 1966
Abstract The annealing behaviour of faulted dislocation loops in quenched zinc has been studied with the aid of the electron microscope. On annealing, it is observed that some of the loops grow rather than shrink, and this has been attributed to the growth of zinc oxide on the foil surface, which results in the formation of vacancies.
P. S. Dobson, Raymond Edward Smallman
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Image Simulation of Dislocation Loops

Proceedings, annual meeting, Electron Microscopy Society of America, 1976
Computer simulation of image contrast is a useful tool in the identification of lattice defects observed in the electron microscope. In order to obtain high quality simulated micrographs, it is necessary either to consume a considerable amount of computer time or to have the micrographs processed through special photographic devices.
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