Crystal Plasticity on the Nano and Micro Scales: Micromechanical Theory and Experiments

Washington State University, Pullman WA

Investigators

Abstract

ABSTRACT: Crystal Plasticity on the Nano and Micro Scales. Micromechanical Theory and Experiments. PI: S. Dj. Mesarovic, School of Mechanical and Materials Engineering, Washington State University A fundamental study of dislocation plasticity in small volumes is proposed. The proposed study will coordinate experiments, discrete dislocation (DD) simulations, and, development and implementation of a micromechanical continuum theory guided by experiments and DD simulations. The existing gaps - between theories and experiments, and, between a continuum theory and its micromechanical foundation (dislocation mechanics), will be closed. The experiments on simple two-dimensional geometries with small number of active slip systems are proposed. In addition to the recently performed wedge microindentation, the constrained shear of a thin film will be performed with subsequent OIM measurements of lattice rotations, lattice curvature and densities of geometrically necessary dislocations. By developing a rigorous thermodynamic foundation of the continuum theory based on dislocation mechanics. This will enable unambiguous continuum interpretation of experimental results and of discrete dislocation simulations. The envisioned research program is integrated with graduate and undergraduate education at MME/WSU.