Effect of compaction roller on layup quality and defects formation in automated fiber placement

Application of automated fiber placement is limited by defects formed in the prepreg tows during the layup process. An extensive experimental study is performed to investigate the effect of compaction roller on the quality of the layup. Five different compaction rollers with different stiffness and architectures were manufactured and employed to dispense prepreg tows at various process conditions. Layup quality was examined and different defects including tow buckling and blister were identified. In addition to automated fiber placement trials, static testing and finite element simulations were performed to probe the pressure distribution and contact width of each roller. This data was used to support and understand the results of the automated fiber placement trials. Results indicate the solid elastomer rollers that are compliant enough to produce the same level of contact width under similar levels of compaction forces are superior to the perforated rollers in terms of achievable layup quality.