Numerical Analysis of a DMA Epoxy-Carbon Composite Study

The results of numerical simulations performed for Dynamic Mechanical Analysis (DMA) measurements of thermal and mechanical (or thermomechanical) properties performed on a model composite structure are presented herein. The simulated elastic response of an epoxy-carbon fibre composite specimen was analysed for a case by which the model specimen was subjected to three-point bending with a free support. The epoxy-carbon fibre composite studied as explained herein exhibited extreme differences between the resilient properties of the epoxy resin matrix and the carbon fibre reinforcement. In addition, the carbon fibre reinforcement was both internally and structurally anisotropic. The numerical simulations were performed to demonstrate a qualitative dependence of the DMA measurement results on a certain structure of the investigated specimen and to determine if the DMA results could be qualified as effective or apparent. A macro-mechanical model of the specimen was developed and had the numerical calculations run with COMSOL/M, a FEM modelling software suite. The carbon fibre reinforcement was modelled with an orthotropic structure of laminar or circular inclusions with different characteristic dimensions. Representative material properties were assumed from the results of proprietary experimental investigations and certain reference literature data. The effect of the composite layers’ configuration and their characteristic dimensions on the evaluated model’s elastic modulus value was also studied. The results presented herein suggested a qualitative agreement with the results of the DMA investigations performed on real-life composite structures. They also proved the effectiveness of the developed numerical simulation methodology, shown herein, in the DMA of micro- and macromechanical phenomena