22: Introduction to Dislocations
- Page ID
- 31603
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Learning Objectives
On completion of this TLP you should:
- understand the nature of dislocations both conceptually and in a real crystal structure
- appreciate the motion of a dislocation under an applied stress
- be aware of the methods that can be used to reveal dislocations in a crystal structure
Before you start
Most of this package assumes no prior knowledge. However, some of the more detailed explanations use the following:
- Miller index notation for specification of crystal planes and directions
- Bravais lattice types
It should be possible to make use of the package even without knowledge of these concepts.
- 22.7: Observing Dislocations
- A number of ways of 'seeing' dislocations in real materials have developed since the 1950s. Only in the last few years have electron microscopy techniques advanced sufficiently to allow the atomic structure around a dislocation to be resolved.