Experimental and numerical investigation of the low-velocity impact behavior in foam-core sandwich panels with manufacturing-induced de-bonding defects using pulsed infrared thermography

This study investigates the influence of manufacturing defects on the mechanical behavior of Carbon Fiber Reinforced Polymer (CFRP) sandwich panels with a Polyvinyl Chloride (PVC) foam core when subjected to low-velocity impact loading. Foam-core sandwich panels were made using the hand layup method with a stacking sequence of [(0/90) 8 /core/(0/90) 8 ] and Teflon layers were inserted between the upper face and core to simulate de-bonding defects. Then, the sandwich panels were subjected to three levels of energy. Energy profile diagrams (EPDs) were plotted to determine the perforation thresholds of the sandwich panels. The non-destructive active pulsed infrared thermography evaluation method was employed for detecting damage in the sandwich panels before and after the drop weight impact test. In this study, simulations were conducted to demonstrate the accuracy of determining de-bonding defects and the low-velocity impact behavior of the sandwich panels. The experimental results from the drop weight tests showed that manufacturing defects affected the low-velocity impact behavior of the sandwich panels, and the experimental results from the active pulsed infrared thermography method showed that this method could identify the number and size of manufacturing defects with high accuracy. Furthermore, the results of the drop weight impact test simulation, such as peak force, were compared with experimental results. The results showed that manufacturing defects affected the low-velocity impact behavior of the sandwich panels.