Plastic Deformation

· Partial dislocations and their associated stacking fault are shown in a transmission electron micrograph of a copper-7% aluminum alloy.
· The diagram shows the arrangement of the dislocations in the region ABCD.
· For Copper the stacking fault energy is about 0.04 J/m² and for Aluminum about 0.2 J/m².
· Observation of stacking faults in these materials show them to have the expected width ratio of 8 : 1, their elastic constants being similar.

From: Hull, "Introduction to Dislocations," Pergamon (1965)