line defect

References

line defect

crystallography

Also known as: dislocation

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June 30, 2026

Quick Summary

In crystallography, a line defect, also known as a dislocation, is an imperfection where atoms are arranged irregularly along a line within a crystal's structure. These defects can significantly influence a solid's mechanical, electrical, and optical properties.1

There are different types of line defects, including:
* Edge dislocations: These occur when an extra plane of atoms is inserted into the crystal structure, or when a row of atoms is missing. This creates a strain in the surrounding atoms.2
* Screw dislocations: These involve atoms arranged in a helical pattern relative to the direction of stress.3

Line defects can either weaken or strengthen a crystal. They are crucial in understanding how materials deform plastically under stress, a process known as slip.14

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ceramic composition and properties
Brittleness
…property owing to imperfections called dislocations within their crystal lattices. There are many kinds of dislocations. In one kind, known as an edge dislocation, an extra plane of atoms can be generated in a crystal structure, straining to the breaking point the bonds that hold the atoms together. If stress…
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…property owing to imperfections called dislocations within their crystal lattices. There are many kinds of dislocations. In one kind, known as an edge dislocation, an extra plane of atoms can be generated in a crystal structure, straining to the breaking point the bonds that hold the atoms together. If stress…
Read More

deformation and flow
Such defects are called dislocations, and they give a crystalline structure the ability to sustain plastic deformations without fracturing. In materials science, a study of the role of dislocations in plastic flow constitutes a major research activity.
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Such defects are called dislocations, and they give a crystalline structure the ability to sustain plastic deformations without fracturing. In materials science, a study of the role of dislocations in plastic flow constitutes a major research activity.
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mechanics of solids
Dislocations
…and displacement fields created by dislocating solids. This involves making a cut in a solid, displacing its surfaces relative to one another by some fixed amount, and joining the sides of the cut back together, filling in with material as necessary. The initial status of this work was simply regarded…
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…and displacement fields created by dislocating solids. This involves making a cut in a solid, displacing its surfaces relative to one another by some fixed amount, and joining the sides of the cut back together, filling in with material as necessary. The initial status of this work was simply regarded…
Read More

materials science
High-temperature materials
All materials contain dislocations. The simplest of these are the result of planes of atoms that do not extend all through the crystal, so that there is a line where the plane ends that has fewer atoms than normal. In metals, the outer electrons are free to move.…
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All materials contain dislocations. The simplest of these are the result of planes of atoms that do not extend all through the crystal, so that there is a line where the plane ends that has fewer atoms than normal. In metals, the outer electrons are free to move.…
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ice
Mechanical properties
The motion of dislocations—that is, of defects or disorders in the crystal lattice—controls the speed of plastic deformation. Dislocations do not move under elastic deformation.
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The motion of dislocations—that is, of defects or disorders in the crystal lattice—controls the speed of plastic deformation. Dislocations do not move under elastic deformation.
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steel
Effects of alloying
…structures to the motion of dislocations. Dislocations are failures in the lattices of crystals that make it possible for metals to be formed. When elements such as nickel are kept in solid solution in ferrite, their atoms become embedded in the iron lattices and block the movements of dislocations. This…
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…structures to the motion of dislocations. Dislocations are failures in the lattices of crystals that make it possible for metals to be formed. When elements such as nickel are kept in solid solution in ferrite, their atoms become embedded in the iron lattices and block the movements of dislocations. This…
Read More