Mapping complex microdefects of porous CFRP-laminates onto structured FE-meshes using the GAUSS-point method

Abstract

The increased usage of composites in the last years demands for cost-efficient manufacturing. Infusion and injection processes seem promising in managing economical and quality issues at the same time. However, these processes are prone to manufacturing defects like porosity. In order to evaluate the effects of porosity, numerical tools like finite element analyses (FEA) along with representative volume elements (RVE) can be used. The classical approach is to model complex defects conformed which usually results in a large number of quadratic tetrahedral elements and a bad numerical performance. Within the scope of this work, a highly efficient method is presented to map complex void morphologies obtained from micro-CT scans of CFRP samples onto RVE with structured, linear meshes. To do this, the GAUSS-point method is used. An algorithm implemented into ABAQUS checks in which material phase the current GAUSS-point lies and adjusts the material properties accordingly. The resulting system of equations can be reduced massively compared to the reference conformed mesh, whereas the results obtained from the GAUSS-point method deviate only slightly from the reference solution.