Acta Mechanica Solida Sinica

, Volume 25, Issue 2, pp 210–220

# The Dislocation Equations of a Simple Cubic Crystal in the Isotropic Approximation—A Solvable Model

Article

## Abstract

The dislocation equations of a simple cubic lattice have been obtained by using Green’s function method based on the discrete lattice theory with the coefficients of the second-order differential terms and the integral terms have been given explicitly in advance. The simple cubic lattice we have discussed is a solvable model, which is obtained according to the lattice statics and the symmetry principle and can verify and validate the dislocation lattice theory. It can present unified dislocation equations which are suitable for most of metals with arbitral lattice structures. Through comparing the results of the present solvable model with the dislocation lattice theory, it can be seen that, the coefficients of integral terms of the edge and screw components we obtain are in accordance with the results of the dislocation lattice theory, however, the coefficient of the second-order differential term of the screw component is not in agreement with the result of the dislocation lattice theory. This is mainly caused by the reduced dynamical matrix of the surface term, which is the essence to obtain the dislocation equation. According to the simple cubic solvable model, not only the straight dislocations but also the curved dislocations, such as the kink, can be investigated further.

## Key words

solvable model dislocation equation Green’s function discrete effect

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© The Chinese Society of Theoretical and Applied Mechanics and Technology 2012

## Authors and Affiliations

1. 1.College of Physics and OptoelectronicsTaiyuan University of TechnologyTaiyuanChina
2. 2.School of Information and EngineeringWenzhou Medical CollegeWenzhouChina
3. 3.School of PhysicsChongqing UniversityChongqingChina