Plastic Deformation

Dislocation Mechanisms for Work Hardening (Strain Hardening)

· Plastic deformation in an ideal elastic-ideal plastic material takes place at the yield stress until the material fails by ductile fracture (red line).

· In a real material, the true stress needed to sustain plastic deformation increases as true strain increases.
· Work hardening (strain hardening) results from the interactions between dislocations during the plastic deformation process.
· Data on single crystals tested in uniaxial tension provides insights into the mechanisms involved.

From: Ashby & Jones, "Engineering Materials 1," Pergamon (1980)