Results 111 to 120 of about 16,684 (165)

Dislocation loops in antimony telluride

Physica Status Solidi (a), 1971
The investigation of the diffraction contrast of large hexagonal dislocation loops in Sb2Te3 suggests that nearly all of them are multiple loops. A model which explains satisfactorily the contrast is described. At elevated temperatures the loops do not shrink but take a circular equilibrium shape.
P . Skalicky, E . Wolfgang
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Crystallography of dislocations and dislocation loops in deformed iron

Philosophical Magazine, 1964
Abstract Crystallographic analyses of dislocations and dislocation loops in deformed b.c.c. iron observed in the electron microscope have been carried out by applying the electron diffraction theory of contrast at dislocations. Dislocations in deformed iron are in the form of tangles, with interspersed clusters of dislocation loops, from the very first
S. M. Ohr, D. N. Beshers
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Energy of hexagonal dislocation loops

physica status solidi (b), 1966
AbstractThe elastic strain energy of an elongated hexagonal dislocation loop is calculated from the stress field of dislocation segments using isotropic elasticity theory. Energies of rhombus dislocation loops and rectangular dislocation loops are presented as limiting cases.
G. C. T. Lxu, J. C. M. Li
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Dislocation loops in diamond

Philosophical Magazine, 1962
Abstract Mat triangular plates of diamond have been thinned sufficiently by oxidation at high temperatures for an examination to be carried out by transmission electron microscopy. By suitably tilting the specimens all the diamonds examined have been shown to contain dislocation loops.
T. Evans, C. Phaal
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Dislocation loops in finite systems

Physical Review B, 1994
The distortions induced by dislocation loops are studied in finite systems. The influence of finite size, D, of the system, surface tension, and surface-bending elastic constant on the nematic-smectic (NA) phase transition is discussed. In thin freely suspended smectic liquid-crystal films the nematic-smectic transition temperature, ${\mathit{T}}_ ...
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Cooperative Nucleation of Shear Dislocation Loops

Physical Review Letters, 2002
The mean elastic interaction between randomly distributed transient subcritical shear loops of the same sign, formed in the presence of an applied shear stress, is the "image stress." This stress is proportional to the volume density of loops and has the same sign as the applied stress.
Y Q, Sun, P M, Hazzledine, P B, Hirsch
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Dislocation loops in irradiated iron

Philosophical Magazine, 1963
IT has been suggested many times that the hardening of iron and steel on irradiation may result from the interaction of glide dislocations with dispersed clusters of point defects. Two observations of such clusters using the technique of transmission electron microscopy have been reported in the literature1,2.
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Residual image contrast of dislocation loops

Physica Status Solidi (a), 1978
The electron microscope images of large dislocation loops lying perpendicular to the electron beam are calculated by applying the image simulation technique. It is found that the residual double arc contrast arising from the g · b × u term exhibits asymmetry which is depth dependent.
J. Narayan, S. M. Ohr
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The Interaction of Straight Dislocations with Dislocation Loops in an Anisotropic Material (Zinc)

Physica Status Solidi (a), 1984
The elastic interactions between straight dislocations and dislocation loops, both unsheared and sheared are studied for an isotropic and anisotropic material, zinc. The total interaction energy and total force between the interacting elements are computed for isotropic and anisotropic materials and conclusions made on the effect of the flexibility of ...
H. M. Eissa, M. M. El-Oker
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Prismatic dislocation loops and concentric dislocation loops in HPHT-grown diamond single crystals

Materials Science and Engineering: A, 2003
Abstract As-grown diamond single crystals grown from Fe–Ni–C system under high temperature–high pressure were examined by transmission electron microscopy. There exist prismatic dislocation loops and concentric dislocation loops in the diamond, which are related to the nonequilibrium nature of the diamond synthesis process.
Long-Wei Yin, Mu-Sen Li, Zeng-Da Zou, Zhi-Guang Gong, Zhao-Yin Hao   +4 more
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