Dislocations force between perpendicular

Fig. 8.23. Interaction force between two perpendicular screw dislocations (adapted from Hartley and Hirth (1965)).

Elastic Forces for Three-Dimensional Dislocation Configurations Use isotropic linear elasticity to compute the elastic forces of interaction between two dislocations oriented as (a) two perpendicular screw dislocations, (b) two perpendicular edge dislocations. 

Here we used the fact that the force is perpendicular on the dislocation line. If the orientation between the stress tensor a, the dislocation line /i and the Burgers vector b is arbitrary, the Peach-Koehler equation... 

Using d and V, the mean distance L between particles may be calculated, which determines the mechanism of reinforcement that prevents the plastic flow this is explained schematically in Figure 2.4. The driving force which pushes the dislocations is provided by the stress ty The force acting on one segment of the row of particles is equal to t bL, where b is the perpendicular dimension. The critical situation occurs when that force is balanced by the line tension T ... 

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