Multi-scale modeling of distortion in the non-flat 3D woven composite part manufactured using resin transfer molding

This paper presents a multi-scale thermo-chemo-mechanical simulation predicting the distortion of a 3D woven composite part manufactured using the Resin Transfer Molding (RTM) process. The multi-scale numerical procedure relied on an anisotropic temperature- and degree of cure-dependent viscoelastic constitutive law whose parameters were obtained from experimental data and a blackbox optimization algorithm. Analytical (at the micro-scale) and numerical (at the meso-scale) homogenization procedures were used to compute the effective coefficients of thermal expansion and chemical shrinkage. An actual 3D woven non-flat composite specimen exhibiting variations in properties and thickness was designed and manufactured using the RTM process. The contoured geometry of the manufactured part was digitized using an industrial optical 3D scanner and compared against the developed multi-scale numerical predictions. It was found that the presented approach was capable of qualitative and, in some cases, quantitative prediction with the highest accuracy ~2.8% of manufacturing induced geometrical distortions.