MICROSTRUCTURE-BASED SIMULATIONS OF QUASISTATIC DEFORMATION USING AN EXPLICIT DYNAMIC APPROACH

Abstract

Microstructure-based simulations of the deformation processes require substantial computational resources due to the necessity of using detailed meshes with a large number of elements. An approach that considerably reduces the computational costs implies simulation of quasistatic deformation within a dynamic approach involving a solution of the motion equations rather than the equilibrium equations. It enables a transition from implicit to explicit time integration providing a significant gain in the computational capacity. In this paper, we show that the explicit dynamic approach can be successfully used in the microstructure-based simulations of quasistatic deformation, considerably reducing the computational costs without losing the information and solution accuracy. The following conditions have to be met to ensure a close agreement between the dynamic and static solutions: (i) the load velocity in the dynamic calculations must be smoothly increased to its amplitude value and then kept constant to minimize the acceleration term appearing in the equation of motion and (ii) the constitutive model employed must describe a quasi-rate-independent response. An examination of the mesh convergence and the strain-rate dependence for a polycrystalline aluminum model has supported this conclusion.