The Elastic Fields Produced by an Infinitesimal Dislocation Loop, an Interstitial Atom, and a Vacancy Moving with Uniform Velocity

ABSTRACTThe elastic fields of a torsional dislocation loop in a homogeneous material are first derived. The solution is based on torsional symmetry. The stress and displacement solutions are then extended to the case of a torsional loop in a bi-material. A main utility of basic dislocation solutions is in fracture mechanics. In particular, circular loop solutions can be used in the modeling of both cylindrical and penny-shaped cracks. In the present study we use them to model a Mode III cylindrical crack via the application of a “distributed-dislocation technique”. Stress intensity factors at the crack tips are presented. The influences of crack radius and material pair on the stress intensity factor of interfacial cracks are investigated.

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Displacement and Plastic Distortion Fields Produced by Dislocations in Anisotropic Media

Journal of Applied Mechanics ◽

10.1115/1.3408967 ◽

1971 ◽

Vol 38 (4) ◽

pp. 865-868 ◽

Cited By ~ 10

Author(s):

T. Mura

Keyword(s):

Dislocation Density ◽

Unique Solution ◽

Integral Method ◽

Anisotropic Media ◽

Fourier Integral ◽

Elastic Fields ◽

Uniform Velocity ◽

Plastic Distortion ◽

History Of ◽

Distribution Of Dislocations

The fundamental relations among dislocation density tensors, plastic distortion tensors, and dislocation flux tensors are introduced by the Fourier integral method. The proposed method is analytical rather than geometrical and powerful for further analysis of elastic fields. This method is applied to find displacement and plastic distortion fields for a given distribution of dislocations in anisotropic media. Since these quantities are not state quantities, the unique solution is obtained by designating a history of creation of the dislocations. In this paper the history is given in terms of the direction of motion in which the dislocations are introduced in the material from infinity with infinitely small uniform velocity.

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Elastic fields of a dislocation loop in a two-phase material

Journal of Elasticity ◽

10.1007/bf00046466 ◽

1971 ◽

Vol 1 (2) ◽

pp. 153-164 ◽

Cited By ~ 52

Author(s):

N. J. Salamon ◽

J. Dundurs

Keyword(s):

Dislocation Loop ◽

Two Phase ◽

Elastic Fields

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Interfacial elastic fields of a 3D dislocation loop in anisotropic bimaterials of finite thickness crystal films

Mechanics of Materials ◽

10.1016/j.mechmat.2017.07.009 ◽

2017 ◽

Vol 113 ◽

pp. 1-18 ◽

Cited By ~ 3

Author(s):

Y.P. Chen ◽

Y.Y. Cai ◽

J.P. Guo ◽

Ernian Pan

Keyword(s):

Dislocation Loop ◽

Finite Thickness ◽

Elastic Fields ◽

Crystal Films ◽

Anisotropic Bimaterials

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Dislocation loop structure, energy and mobility of self-interstitial atom clusters in bcc iron

Journal of Nuclear Materials ◽

10.1016/s0022-3115(99)00166-x ◽

2000 ◽

Vol 276 (1-3) ◽

pp. 33-40 ◽

Cited By ~ 154

Author(s):

B.D Wirth ◽

G.R Odette ◽

D Maroudas ◽

G.E Lucas

Keyword(s):

Dislocation Loop ◽

Interstitial Atom ◽

Loop Structure ◽

Atom Clusters ◽

Bcc Iron

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Image Contrast of Dislocation Loops Near a Free Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100077888 ◽

1977 ◽

Vol 35 ◽

pp. 52-53

Author(s):

S. M. Ohr

Keyword(s):

Free Surface ◽

Dislocation Loop ◽

Image Contrast ◽

Stress System ◽

Shear Stresses ◽

Dislocation Loops ◽

Axially Symmetric ◽

Displacement Fields ◽

Elastic Fields ◽

Analytical Expressions

The image contrast of dislocation loops computed in the past has made use of the displacement fields which do not take into account the presence of stress- free foil surfaces. The free surface modifies the elastic fields around a dislocation loop and hence can influence the image contrast observed in the electron microscope. The effect can be significant particularly when the loops lie close to one of the foil surfaces. In general, the elasticity problem of dislocation loops that takes the free surface into account is difficult to handle mathematically. In the present paper, the method of Bastecka1 was extended to obtain explicitly the analytical expressions for the displacement fields around a pure edge circular dislocation loop lying parallel to the foil surface. In this method, the stress fields of an image dislocation loop and another axially symmetric stress system were added in order to eliminate the normal as well as shear stresses at the surface.

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