Failure Mechanisms

· The green area on the deformation map is the region of elastic response, the region favored for stable device design.

· Dislocation glide controls deformation at low temperatures and high stress levels. The energy of the dislocation depends on its location in the slip plane as shown.
· Glide is thermally assisted, the dislocations needing to overcome the Peierls barrier to their motion in the glide plane. Stress lowers the barrier in one motion direction and increases it in the opposite direction.

From: Courtney, "Mechanical Behavior of Materials,"
McGraw Hill (1990)