FEM–CT integrated design for multiscale damage analysis of hydroformed magnesium-based alloy tubular product

Abstract

Damage analysis of the material, such as magnesium-based alloy, is important to investigate the micro-defects and to account for material instability. These micro-defects can be investigated from a sliced test specimen by the mechanical slicing method. This destructive method of measurement is not only laborious but also costly. The surface or interior microstructure of the test specimens may be destroyed. In this study, a finite element method (FEM) and computed tomography (CT) integrated design of multiscale damage analysis was used to measure the micro-defect distributions from the magnesium-based alloy tubular component (AZ31B) formed by the hydroforming process. A critical linkage between the microscopic and macroscopic scales was established. Damage variables, such as the spatial distribution, or void size, were recorded by the digital image processing tool. The representative volume element (RVE) models were reconstructed by the CAD tool from the CT image. FEM simulation tool (e.g. ABAQUS) was employed to obtain the results of mechanical properties from the RVEs at different void fractions. The experimental and FEM simulation results were compared to study the material behaviours. Different void fractions of micro-voids were simulated to study the deformation and Von Mises stress of the RVE. The proposed method can contribute to various industrial applications for rapid damage assessment.