“…They found that compared to the panels without repass (void content of 0.42%), the void content decreased to 0.28 and 0.23% after once and twice repass, respectively. In addition, Chanteli et al 47 reported a similar trend as well, the void content decreased from 4.21 to 3.46% after once repass. Therefore, the repeated application of temperature and pressure can effectively reduce the void content.Figure 9.Cross-sectional morphology and void content of CF/PPS composites at different consolidation forces of: (a) 500 N; (b) 1000 N; (c) 1500 N; and (d) 2000 N (Related to sample 6#–9#).Figure 10.Cross-sectional morphology and void content of CF/PPS composites at different placement speeds of: (a) 60 mm/s; (b) 100 mm/s; and (c) 200 mm/s (Related to sample 3#–5#).Figure 11.Cross-sectional morphology of laminate 1#.…”
In situ consolidation of thermoplastic composites can be realized through laser-assisted automated fiber placement (AFP) technology, and the properties of composites were significant affected by the process parameters. In this work, the effects of process parameters on the properties of continuous carbon fiber–reinforced polyphenylene sulfide (CF/PPS) composites manufactured by laser-assisted AFP were investigated. Four-plies CF/PPS prepreg was laid under the combination of different process parameters and the morphology, void content, crystallinity, and inter-laminar shear strength (ILSS) of the composites were characterized. It turned out that the resin distribution on the surface of the composites could be significantly improved by increasing the laser temperature and compaction pressure. The highest crystallinity of the composites reached 46% at tool temperature of 120°C while the value was only 18% when the tool temperature was 40°C. Meanwhile, with the increasing compaction force ranging of 500–2000 N, the void content of the composites decreased obviously. The ILSS was evaluated through double notch tensile shear test. The results indicated that the mechanical properties of the composites were dominated by void content rather than crystallinity.
“…They found that compared to the panels without repass (void content of 0.42%), the void content decreased to 0.28 and 0.23% after once and twice repass, respectively. In addition, Chanteli et al 47 reported a similar trend as well, the void content decreased from 4.21 to 3.46% after once repass. Therefore, the repeated application of temperature and pressure can effectively reduce the void content.Figure 9.Cross-sectional morphology and void content of CF/PPS composites at different consolidation forces of: (a) 500 N; (b) 1000 N; (c) 1500 N; and (d) 2000 N (Related to sample 6#–9#).Figure 10.Cross-sectional morphology and void content of CF/PPS composites at different placement speeds of: (a) 60 mm/s; (b) 100 mm/s; and (c) 200 mm/s (Related to sample 3#–5#).Figure 11.Cross-sectional morphology of laminate 1#.…”
In situ consolidation of thermoplastic composites can be realized through laser-assisted automated fiber placement (AFP) technology, and the properties of composites were significant affected by the process parameters. In this work, the effects of process parameters on the properties of continuous carbon fiber–reinforced polyphenylene sulfide (CF/PPS) composites manufactured by laser-assisted AFP were investigated. Four-plies CF/PPS prepreg was laid under the combination of different process parameters and the morphology, void content, crystallinity, and inter-laminar shear strength (ILSS) of the composites were characterized. It turned out that the resin distribution on the surface of the composites could be significantly improved by increasing the laser temperature and compaction pressure. The highest crystallinity of the composites reached 46% at tool temperature of 120°C while the value was only 18% when the tool temperature was 40°C. Meanwhile, with the increasing compaction force ranging of 500–2000 N, the void content of the composites decreased obviously. The ILSS was evaluated through double notch tensile shear test. The results indicated that the mechanical properties of the composites were dominated by void content rather than crystallinity.
“…However, specimens consolidated using autoclave showed the best performance for all the properties studied, especially for the mechanical properties. Comparing the findings from [95] and [94], it can be seen that the effect of the repass treatment depends on the heat source used. For laser ISC, due to the high heating and cooling rate, a repass treatment was required to increase the crystallinity.…”
Section: Studies On Factors Affecting In Situ Consolidation Qualitymentioning
confidence: 96%
“…Factors affecting the morphology include the degree of crystallinity, spherulite size and crystalline orientation [8]. Many researchers use the degree of crystallinity as a means of studying the morphology [51,53,94,95]. For PEEK, tensile strength and stiffness increases with increasing crystallinity but fracture toughness decreases at the same time [8].…”
Section: Modeling Crystallization and Other Aspects Of Frtp In Situ Consolidationmentioning
confidence: 99%
“…Another study on the effect of repass in AFP with laser ISC was conducted by Chanteli et al [94]. Four repass methods were compared, namely single repass, double repass, perpendicular repass (repass applied perpendicular to the fiber direction) and tool-side repass (repass applied on the ply already laid on the tool).…”
Section: Studies On Factors Affecting In Situ Consolidation Qualitymentioning
confidence: 99%
“…Few studies have been conducted on the fabrication of complex FRTP composite components using AFP with ISC. Clancy et al studied the fabrication of variable angle tow (VAT) laminates using AFP with laser ISC [94,112]. The authors showed that the AFP process can produce carbon/PEEK VAT laminates with no significant defects for a steering radius of 400 mm and above.…”
Section: Studies On Factors Affecting In Situ Consolidation Qualitymentioning
Fiber reinforced thermoplastic composites are gaining popularity in many industries due to their short consolidation cycles, among other advantages over thermoset-based composites. Computer aided manufacturing processes, such as filament winding and automated fiber placement, have been used conventionally for thermoset-based composites. The automated processes can be adapted to include in situ consolidation for the fabrication of thermoplastic-based composites. In this paper, a detailed literature review on the factors affecting the in situ consolidation process is presented. The models used to study the various aspects of the in situ consolidation process are discussed. The processing parameters that gave good consolidation results in past studies are compiled and highlighted. The parameters can be used as reference points for future studies to further improve the automated manufacturing processes.
The continuous carbon fiber‐reinforced polyether ether ketone (CCF/PEEK) composites have been widely utilized in aerospace structures due to their excellent properties. However, the main load‐bearing structure in the next‐generation aircraft needs to withstand high temperatures up to 200°C, and the mechanical properties of CCF/PEEK composites show significant time‐/temperature‐dependence due to the viscoelastic nature of the PEEK matrix. Therefore, accurate predictions of the mechanical performance of CCF/PEEK composites under high‐temperature service conditions are the key issue for structural safety and life assessments and have therefore become a recent research focus. To address these challenges, this study established a bottom‐up analysis framework for the CCF/PEEK composites and employed the theoretical model and the finite‐element representative volume element (FE‐RVE) method to investigate the anisotropic viscoelastic properties of CCF/PEEK composites. We first built an anisotropic viscoelastic model of the unidirectional CCF/PEEK composites by integrating the generalized Maxwell into the bridging model. Upon this foundation, we further developed a viscoelastic laminate model capable of accurately predicting the thermoviscoelastic properties of multidirectional laminates. To verify the developed model, different kinds of FE‐RVEs were built and analyzed. Overall, there is good agreement among the model predictions, the FE‐RVE simulations, and the experimental results within a temperature range of 25–250°C. The developed model can be used to design the high‐temperature performance of CCF/PEEK composites with different fiber volume fractions, laminated configurations, or loading directions.Highlights
An anisotropic viscoelastic model of the unidirectional (UD) continuous carbon fiber‐reinforced polyether ether ketone (CCF/PEEK) composites is built.
The viscoelastic laminate composite model is developed based on the UD CCF/PEEK composites model.
The finite element representative volume element (FE‐RVE) simulation with fibers in a hexagonal or random array has better accuracy compared with the experimental results.
The FE‐RVE simulation and the experimental results verified the developed model from 25°C to 250°C.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
