Chapter/Index: Introduction | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | Appendix
In general, in order to create a perfect dislocation in a crystal, the Burgers vector has to be a lattice vector, connecting equivalent lattice points (e.g. for CsCl it can be <100> but cannot be 1/2<111>, and for NaCl it can be 1/2<110> but cannot be 1/2<100>). The energy of the dislocation is usually proportional to the square of its Burgers vector. Therefore, in most crystal structures, only the dislocations with the Burgers vectors corresponding to the shortest lattice vectors are energetically stable, while the dislocations with Burgers vectors of multiple perfect Burgers vectors are unstable. Table 1995a. Burgers vectors (b) of perfect and partial dislocations in body centered tetragonal (bct) structure on (111) planes.
Table 1995b. Other characteristics of Burgers vectors.
[1] G. Thomas and M. J. Goringe: Transmission Electron Microscopy of Materials (Wiley–Interscience, New York 1979).
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