Burger’s circuit

Draw a Burger s circuit and identify the direction of dislocation propagation. 

Figure 1.32 Burger s circuit around an edge dislocation. From Z. Jastrzebski, The Nature and Properties of Engineering Materials, 2nd ed. Copyright 1976 by John Wiley Sons, Inc. This material is used by permission of John Wiley Sons, Inc.

You can start the clockwise path, called the Burger s circuit, anywhere, as long as you entirely enclose the dislocation with the circuit. 

Figure 3-2. Screw dislocation Burgers vector b with Burgers circuit, s = direction of screw dislocation line.

Fig. 1.18. Atomic resolution transmission electron micrograph of an interface between GdTe and GaAs where the misfit strain is relaxed by the introduction of edge dislocations. The letters S and F refer to start and finish for the Burgers circuit around the dislocation. The bright white spots correspond to atomic positions and the fuzzy white clusters at the interface correspond to the cores of the dislocations. Reproduced with permission from Schwartzman and Sinclair (1991).

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