Composites with excellent thermomechanical and thermochemical properties are urgently needed in the aerospace field, especially for structural applications under high-temperature conditions. Carbon fiber-reinforced Si-based composites are considered the most promising potential high-temperature materials due to their excellent oxidation resistance and ablative behaviors, good structural designability, and excellent mechanical properties. The reinforcement of the relevant composites mainly involves carbon fiber, which possesses good mechanical and temperature resistance abilities. In this paper, the ablation behaviors and mechanisms of related composites are reviewed. For carbon fiber-reinforced pure Si-based composites (C/SiM composites), the anti-ablation mechanism is mainly attributed to the continuous glassy SiO₂, which inhibits the damage of the substrate. For C/SiM composite doping with refractory metal compounds, the oxides of Si and refractory metal together protect the main substrate from ablation and oxidation. Moreover, in addition to thermochemical damage, thermophysical and thermomechanical behavior severely destroy the surface coating of the substrate.

Carbon fiber reinforced plastics (CFRPs) are widely used in the aerospace, automotive, and construction industries. CFRP prepregs (intermediate products) are generally used in CFRP production, with a large number of prepreg cut‐offs being discarded during cutting processes. There is strong demand for a method for recycling carbon fiber prepreg cut‐offs. This paper proposes a method for recycling such material, which is characterized by low cost and high added value, in order to foster the development of a recycling‐oriented society. We prepare carbon tapes (CTs) by cutting discarded cut‐offs according to their size so as to maximize fiber length. Using a simple water CT dispersion method, we fabricate uniform CT sheets and mold a recycled CT‐reinforced composite (R‐CT‐RC). Sample prototyping and mechanical characteristic testing indicate that this R‐CT‐RC is characterized by low recycling cost and desirable mechanical properties. Recycled CT‐reinforced composite with thermoplastic (R‐CT‐RC/TP), which is prepared by adding thermoplastic resin between CTs, can be re‐molded and therefore readily re‐recycled.

Porous carbon nanofibers (PCNFs) with excellent physical and chemical properties have been considered candidate materials for electrodes used in supercapacitors. Herein, we report a facile procedure to fabricate PCNFs through electrospinning blended polymers into nanofibers followed by pre-oxidation and carbonization. Polysulfone (PSF), high amylose starch (HAS), and phenolic resin (PR) are used as three different kinds of template pore-forming agents. The effects of pore-forming agents on the structure and properties of PCNFs have been systematically studied. The surface morphology, chemical components, graphitized crystallization, and pore characteristics of PCNFs are analyzed by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and nitrogen adsorption and desorption test, respectively. The pore-forming mechanism of PCNFs is analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Fabricated PCNF-R have a specific surface area as high as ~994 m²/g, a total pore volume as high as ~0.75 cm³/g, and a good graphitization degree. When PCNF-R are used as active materials to fabricate into electrodes, the PCNF-R electrodes show a high specific capacitance ~350 F/g, a good rate capability ~72.6%, a low internal resistance ~0.55 Ω, and an excellent cycling stability ~100% after 10,000 charging and discharging cycles. The design of low-cost PCNFs is expected to be widely applicable for the development of high-performance electrodes for an energy storage field.

Two-dimensional (2D) braided composites have excellent structural integrity and damage tolerance. Currently, there are few researches focused on the effect of temperature on tensile failure behaviors of 2D braided composites. In this study, 2D biaxial braided composites with different fiber materials were prepared, and the tensile properties and failure mechanisms of these braided composites at different temperatures were studied by means of the tensile test and the high-definition charge coupled device optical microscope. The results show that temperature has significant effects on the tensile properties and fracture damage of 2D braided composites. As the temperature increases, the tensile properties of the two braided composites decrease obviously, and their external fracture failure becomes subtle, while their internal deformation damage becomes significant. Moreover, the differences between the two fibers in tensile fracture behaviors of composites can be more conspicuously observed at higher temperatures.

Background: Nanofiber’s productivity plagues nanofibrous membranes’ applications in many areas. Herein, we present the needle-disk electrospinning to improve throughput. In this method, multiple high-curvature mentals are used as the spinning electrode.Methods: Three aspects were investigated: 1) mechanism elucidation of the needle-disk electrospinning; 2) parameter optimization of the needle-disk electrospinning; 3) productivity improvement of the needle-disk electrospinning.Results: Results show that high-curvature electrode evokes high electric field intensity, making lower voltage supply in spinning process. The needle number, needle length and needle curvature synergistically affect the spinning process and nanofiber morphology. Additionally, higher disk rotation velocity and higher voltage supply can also result in higher nanofiber’s productivity.Conclusion: Compared with previous patents related to this topic, the needle-disk electrospinning is featured with the merits of high throughput, low voltage supply, controllable spinning process and nanofiber morphology, benefiting the nanofiber practical industrial employment and further applications of nanofiber-based materials.