A dislocation model for a weak link at an intergrain boundary with a misorientation angle, θ, was developed under the assumption of order-parameter suppression in regions which were subjected to high stresses. The stress fields at intergrain boundaries with randomized dislocations (resulting from thermal fluctuations) led to a rapid (exponential with respect to θ) lowering of the critical current. The predictions agreed with experiment.

Tilt Boundary in High-Temperature Superconductors as a Set of Randomly Distributed Dislocations. E.Z.Meilikhov: Czechoslovak Journal of Physics, 1996, 46[S2], 1015-6