Strain hardening of crystalline materials

Abstract

To describe the work hardening process of crystalline materials in uniaxial deformation, a gradient-one-internal-variable model (GM1) constructed in the basis of the Kocks-Mecking model is proposed. The time and temperature dependence of flow stress is accounted via grain boundary migration, and the migration is related to annihilation of extrinsic grain boundary dislocations (EGBD’s) by climb via lattice diffusion of vacancies at the triple points. To model the polycrystalline behavior of commercially pure nickel (from a composite point of view) by means of the finite element method, virtual specimens with dimen­sions in the range 3-25 μm should be used.

Keywords

• Dislocaciones
• borde de grano
• método de los elementos finitos
• comportamiento policristalino