Abstract Thermal residual stress generated during curing is known to be detrimental mechanical performance of a carbon composite. Fiber prestressing technique has been developed for decades counterbalance these negative effects. Although there have some achievements in development the prestress mechanisms, are mainly based on extrapolations from macroscopic characterizations, lack direct evaluation in‐situ in‐plane strain or evolution order reveal impact induced by different methods. Here,...

Abstract Bistable composite cylindrical structures have been developed over the last four decades, and show great potential for shape morphing applications, especially in aerospace. Their bistabilities are known to be induced by unsymmetric layups, while governing factors on geometries viscoelastic mechanics remain an enigma. Here, we investigated intricate relationship between structural geometry stable of a bistable structure. A polylactic acid (PLA)‐based carbon laminate was prepared...

Abstract The composite segmented tools, used as the internal mandrel, are crucial in integrated curing process of aerospace tanks. Their precise manufacturing demands stringent requirements. Current studies lack reports on simulation and optimization making it challenging to provide effective guidance for high‐quality This study focuses tools a Φ3.35 m liquid oxygen tank. kinetics equations thermophysical properties T800/epoxy composites were tested fitted. Finite element prediction models...

Abstract Bistable composite cylindrical structure is a thin-walled shell, which stable at both its extended and coiled configurations, offering large shape morphing capabilities without structural damage, has been successfully applied in deployable structures launched in-orbit. Smart design provides new freedom flexibility for space mechanics to reduce weight complexity. Here, we presented novel magnetic activated bistable structure, where the fundamentals on critical driving boundaries were...

Abstract The integrated manufacturing of aerospace composite cryogenic tanks is crucial for enhancing payload efficiency, reducing costs, and leading the industry upgrade. Composite segmented tool, which balances internal support mold surface, must not only meet requirements disassembly demolding but also ensure sufficient stiffness without deformation under loads like winding tension curing shrinkage during tank formation. This article addresses challenge faced by tool with uniformly thick...

Interlaminar properties are one of the most important indicators thermoplastic composite quality. A series laminates with different moulding process parameters were prepared by unidirectional carbon fibre-reinforced polyether ether ketone (CF/PEEK) prepreg to explore influence on interlaminar CF/PEEK laminates. The three parameters, pressure, temperature, and holding time shear strength (ILSS) [0/90] 8 was studied. failure modes specimens under compared, correlation between ILSS analysed....

As an attractive alternative to the traditional autoclave curing process, microwave has been widely used for manufacturing high-performance composites. However, nonuniform temperature distribution during composite is main problem faced by which limits its application in aerospace industry. This paper studied regulating effects of cavity structure and mechanical optimization methods on uniformity field numerical analysis finite element simulation, octagonal heating device with multi-microwave...

Vibration pretreatment microwave curing is a high-quality and efficient composite out-of-autoclave molding process. Focusing on interlaminar shear strength, the effects of temperature, time vibration acceleration performance components were analyzed sequentially using orthogonal test design method; scanning electron microscope (SEM) optical digital (ODM) used to analyze void content fiber-resin bonding state specimens under different processes. The results show that influence order process...

Abstract Compared to composite components prepared by traditional thermal process, microwave‐cured laminates exhibit superior mechanical properties under the same heating cycle, indicating a unique mode that differs from air circulation. To progressively replace curing process with microwave technology in aerospace composites manufacturing field, it is crucial elucidate mechanism of materials. In this study, absorbing performance both carbon fibers and epoxy resins was systematically...

Abstract In this study, the differential scanning calorimetry (DSC) tests were performed to measure nonisothermal crystallization behavior of carbon fiber reinforced polyether ether ketone (CF/PEEK) composites under different cooling rates. The characteristic parameters obtained, and model was established. temperature range material at rates predicted by model. unidirectional laminates fabricated in range. results showed that shifted a lower with increase rate, established consistent DSC...

Abstract The elastic fiber prestressing (EFP) technique has been developed to balance the thermal residual stress generated during curing of a polymeric composite, where continuous fibers were prestretched under either constant or strain throughout process. tension was only removed after resin fully cured. It demonstrated that EFP is able enhance shear properties while underlying mechanics still unknown. Here, we investigated multiscale failure mechanisms induced by within carbon composite....

Abstract An operating window, which is bounded by two temperatures and draw ratios, defines the stable defect‐free stretching region of a polymer film. Physical properties including coefficient thermal expansion (CTE), birefringence, Young's modulus recyclable polyimide (PIR) film were measured under conditions. While values birefringence increased with increasing stress in machine direction, CTE was found to decrease. A semiempirical model for prediction conditions developed, from could be...

The presence of voids and delamination are common structural defects in the manufacturing process carbon fiber‐reinforced plastics (CFRPs) structures. reduction quality mechanical properties caused by such will restrict extensive application composite materials engineering field. Therefore, this work reports experimental research analysis on effect random vibration applied to curing system CFRP laminates, mainly aiming at void content improvement performances under low cure pressures. Range...

In the manufacturing process of carbon fiber-reinforced plastics composites, if cure pressure that can form hydrostatic resin is transferred inhomogeneously to interior composite structures, critical imperfections such as voids and delamination which damage mechanical properties restrict subsequent use will be formed. Therefore, present work reports experimental research analysis on effect random vibration applied curing system plastic laminates, mainly aiming at reduction void content...