Fiber print-through effect is a limitation to the use of carbon fiber-reinforced composites in space applications, namely, mirror telescopes. Replica method is used for the production of lightweight telescope mirrors. However, this method requires a polished mandrel, increasing considerably the final cost. In this work, we report a cheaper and simpler alternative production method, which consists in the addition of a carbon nanotube filled epoxy resin layer on the surface of carbon reinforced composites, in order to reduce fiber print-through of the materials. The influence of different carbon nanotube functionalizations, concentrations, and dispersion levels are also assessed. The surface properties are evaluated by interferometry (roughness and waviness) and scanning electron microscopy (morphology). The results show that the waviness, roughness, and consequently fiber print-though are considerably reduced with the addition of a thin layer of nonfunctionalized carbon nanotubes.
Presents technologies and key concepts to produce suitable smart materials and intelligent structures for sensing, information and communication technology, biomedical applications (drug delivery, hyperthermia therapy), self-healing, flexible memories and construction technologies. Novel developments of environmental friendly, cost-effective and scalable production processes are discussed by experts in the field.
The rapid expansion of space exploration has increased the demand for lightweight structural materials capable of maintaining performance under extreme thermal conditions. Carbon fibre-reinforced polymers (CFRPs) offer high specific strength and low density; however, their application in cryogenic environments remains challenging due to the brittleness of epoxy matrices, which are susceptible to cracking at low temperatures and under thermal cycling. In this work, two strategies were investigated to improve the damage tolerance of epoxy nanocomposites: (i) the use of a biscitraconimide-based (BCI) resin and (ii) the incorporation of methyl methacrylate–butadiene–styrene (MBS) core–shell particles. Low additive contents were evaluated to identify formulations compatible with prepreg manufacturing. The incorporation of 2 wt.% of MBS core–shell particles significantly improved the impact resistance of the nanocomposites and was selected for CFRP laminate production. When applied to CFRPs, the modified matrix maintained the overall tensile behaviour while increasing the interlaminar fracture toughness by 102% and 122% at room (RT) and cryogenic temperatures (CT), respectively. These findings demonstrate that matrix modification using low-content toughening is an effective strategy to enhance the cryogenic performance of CFRPs, contributing to the development of lighter and more resilient composite structures for next-generation space systems.
4 December 2018 in Science and Technology of Materials