What is edge dislocation and screw dislocation defect?
Dislocations are another type of defect in crystals. Dislocations are areas where the atoms are out of position in the crystal structure. Dislocations are generated and moved when a stress is applied. The motion of dislocations allows slip – plastic deformation to occur.
Edge dislocations
The edge defect can be easily visualized as an extra half-plane of atoms in a lattice. The dislocation is called a line defect because the locus of defective points produced in the lattice by the dislocation lies along a line. This line runs along the top of the extra half-plane. The inter-atomic bonds are significantly distorted only in the immediate vicinity of the dislocation line.
Screw Dislocations
There is a second basic type of dislocation, called screw dislocation. The screw dislocation is slightly more difficult to visualize. The motion of a screw dislocation is also a result of shear stress, but the defect line movement is perpendicular to the direction of the stress and the atom displacement, rather than parallel.
Dislocations are another type of defect in crystals. Dislocations are areas where the atoms are out of position in the crystal structure. Dislocations are generated and moved when a stress is applied. The motion of dislocations allows slip – plastic deformation to occur.
Edge dislocations
The edge defect can be easily visualized as an extra half-plane of atoms in a lattice. The dislocation is called a line defect because the locus of defective points produced in the lattice by the dislocation lies along a line. This line runs along the top of the extra half-plane. The inter-atomic bonds are significantly distorted only in the immediate vicinity of the dislocation line.
Screw Dislocations
There is a second basic type of dislocation, called screw dislocation. The screw dislocation is slightly more difficult to visualize. The motion of a screw dislocation is also a result of shear stress, but the defect line movement is perpendicular to the direction of the stress and the atom displacement, rather than parallel.
