The stress field, strain energy and interaction force were calculated for an isolated pair of straight parallel screw dislocations, one or both of which was associated with micropipes. The effect of the attraction of 2 dislocated micropipes (or a dislocated micropipe and a full-core screw dislocation) with Burgers vectors of the same sign was examined in detail. An analytical expression for the critical distance below which a dislocated micropipe attracted a full-core screw dislocation was found. It was shown that 2 parallel dislocated micropipes with same-sign Burgers vectors could attract each other if the distance between the micropipes was small enough and the ratios of the micropipe radii and the Burgers-vector magnitudes were sufficiently different. The stress field and strain energy of a dislocated micropipe near to a planar free surface, and the force of the interaction between the micropipe and the free surface were also found.

Elastic Interaction of Micropipes in Crystals. M.Y.Gutkin, A.G.Sheinerman: Physica Status Solidi B, 2002, 231[2], 356-72