Duality of dislocation content of grain boundaries

摘要: The Frank–Bilby equation (FBE) can give many solutions for the dislocation content of a grain boundary (GB); most them are considered to have little physical reality except in limited ranges angles which characterize low-angle GBs. We explore two such solutions, each is an accurate description different tilt GB with same axis. develop model that uses predict coupling factor between normal motion and shear strain produced by any (low- or high-angle) GB. Within this model, FBE rise possible modes coupled under stress differ direction motion. Using molecular dynamics simulations we confirm our model. find positive and/or negative all misorientation angles, gives predictions even high-angle GBs where individual dislocations cannot be resolved. At low temperatures dual behaviour ...