Measurement of Residual Stress in Composites Using Central Hole Drilling and Digital Image Correlation Methods

Residual stress measurement is important in composite components. Due to the non-uniform structure of the composite components, the measurement of residual stress in these components cannot be easily performed. In this study, the composite components of polyester resin with glass fiber were presented as a novel structure for a vehicle segment. These materials are manufactured by hand layup method and will generate residual stresses after curing. To calculate the number of residual stresses generated in these parts, the combined central hole drilling-digital image correlation method was used. This method has advantages over drilling by installing a rosette strain gauge. To measure the residual stresses of the desired piece, the drill was positioned on the set, and three points of bending have been done. Then the experimental test conditions are simulated in the ANSYS finite element software. By comparing the results of the experimental test and software simulation, the residual stress values ​​in composite components were calculated with good accuracy.