INFLUENCE OF POWDER-EPOXY TOWPREGGING LINE PROCESSING PARAMETERS ON TOWPREG CONSOLIDATION

A novel powder-epoxy towpregging production line enabled the production of low-cost towpreg due to its high-speed capabilities-achieved due to the intrinsic nature of powder systems. Understanding the co-dependencies of the manufacturing parameters is paramount to obtain high-quality towpreg of ideal Fibre Volume Fraction (FVF) and void content. In this study, towpregs were produced at different combinations of production temperature, speed, and line tension. FVF and void content of sample towpregs were measured with an analytical balance and density measurement kit, respectively. Additionally, statistical analyses with a Scanning Electron Microscope (SEM) and image processing through ImageJ software were conducted to characterise towpreg composition and cross-sectional area morphology. The differences in FVF and void content on towpreg samples revealed a trend of powder-epoxy flow with respect to its processing parameters. Monitoring the experimental parameters co-dependencies of the tapeline will allow for the production of higher quality tape. Generally, consolidation improved at higher heating temperature and line tension, as the increasing temperature lowered powder-epoxy viscosity, while increasing tension improved fibre spreading, enhancing the powder-epoxy flow into fibres. Increasing line speed resulted in a rise in both FVF and void content as tows spent less time in the powder deposition and melting sections.