Effect of twin boundary migration on fracture toughness of nano-twinned metals

A model is proposed that describes the effect of twin boundary migration in fracture toughness of nanotwinned solids. Within the model, twin boundary migration occurs under the action of high stress fields acting near the crack tip and is accompanied by the formation of the quadrupoles of wedge disclinations. It is shown that twin boundary migration hinders crack growth and thereby increases fracture toughness of nanotwinned solids.