Plastic Deformation

Dislocation Interactions with Point Defects

· Impurity atoms in substitutional sites may have dimensions different from those of the host atoms.
· Lattice distortion around these impurity sites creates a stress field that interacts with edge dislocations.
· Small impurities favor the compression region around the dislocation line, large impurities the tension region. These interactions increase the yield stress of the material.

From: Callister, "Materials Science & Engineering," Wiley (1994)