Critical Thickness Theory Applied to Micromechanical Testing

摘要: Critical thickness theory for the plastic deformation of small stressed volumes is reviewed, with particular emphasis on its application to size effect in common micromechanical testing methods, foil flexure, wire torsion, and compression tension micropillars wires. Key predictions which distinguish from others are that plasticity initiates throughout a finite volume when strain-thickness product or strain-volume integral exceeds critical value related Burgers vector; misfit geometrically necessary dislocations will generally be found outside this volume; intrinsic bulk strength material not changed by effect. Experiments designed test these briefly described.