Damage Assessment of Sheet Molding Compound Composites

The investigation focuses on the initiation and progression of damage in SMC (Sheet Moulding Compound) composites subjected to tension. These composites consist of a polyester matrix reinforced with randomly oriented short C glass fibers. Damage monitoring is conducted using the acoustic emission technique. To assess the influence of surface density on damage in SMC, three series of composites with surface concentrations of 300 g/m2, 450 g/m2, and 600 g/m2 are tested. Based on stress-strain curves, the main mechanical properties of the different composites are determined. Additionally, the analysis of the collected acoustic emission data enabled us to determine the damage thresholds in the different studied composites. While tensile tests and the acoustic emission technique allowed us to determine important composite parameters, further research is necessary to comprehensively discern the various damage modes.