MODIFIED DISLOCATION MODEL OF INTERGRAIN TILT BOUNDARIES IN HTSC

Stress fields at the intergrain boundaries of three different types (s ymmetric and asymmetric tilt boundaries with a periodic system of edge dislocations, and a symmetric system with randomized edge dislocation s) are calculated. Based on these calculations the angular dependence of intergrain critical currents in superconductors is found. It turns out that an adequate description of the superconductive features of th e boundaries could only be obtained in the framework of randomly distr ibuted dislocations.