The net interaction force between two skew dislocations in an anisotropic linear elastic bimetallic medium

Barnett, in 1998. considered the problem of two skew dislocations in an ani sotropic elastic half-space, each dislocation being parallel to the half-sp ace boundary (which was taken as traction-free). He showed that the net int eraction force of one dislocation on the other is independent of the separa tion of the dislocations. Rather incredibly, if the dislocation closest to the half-space boundary is denoted as (1) and the other skew dislocation is denoted as (2), Barnett deduced that the net interaction force of (1) on ( 2) vanishes, while the total interaction force of (2) on (1) is exactly twi ce the net force which (2) exerts on (1) in an infinite medium! The present work examines two skew dislocations in two perfectly bonded anisotropic ha lf-spaces (one half-space may be doubly dislocated or each half-space may c ontain one dislocation). We show that there is an additional contribution ( beyond that given by the half-space: result) to the net interaction force e xerted by one dislocation on the other, which is also separation-independen t; essentially each dislocation experiences an additional contribution to t he net interaction force which is the same as if the other dislocation were located at the interface between the two half-spaces. This additional cont ribution to the net force is 'almost' explicit, requiring only a computatio n of the admittance matrices of the Stroh formalism for each half-space. (C ) 2000 Elsevier Science S.A. All rights reserved.