Effect of Zr/Gnp hybrid filler on thermal and ablation properties of carbon‐epoxy composites

• Published in: Polymer composites 2021-02, Vol.42 (2), p.642-651
• Main Authors: Subha, Sivakumar, Sairam, Vadapalli Naga Venkata, Pal, Yash
• Format: Article
• Language: English
• Subjects: Ablation; ablation behavior; Carbon; Carbon fiber reinforced plastics; Carbon fibers; Carbon-epoxy composites; Chemical synthesis; Fillers; Flexural strength; Graphene; graphene nanoplatelets (Gnp); Morphology; Oxidation; Oxidation resistance; thermal decomposition; Thermal stability; Thermogravimetry; Zirconium dioxide
• ISSN: 0272-8397; 1548-0569
• DOI: 10.1002/pc.25854

In this work, the Zirconia (Zr) particles were coated with graphene nanoplatelets (Gnps) using the wet chemical synthesis process and sintered at 500°C and 900°C. At sintering temperature of 900°C, the Zr coated with 0.25 wt% Gnp fillers exhibited better oxidation resistance. Thus, the carbon epoxy (C‐Ex) composites containing Zr/Gnp, 0.25 wt%, were fabricated by the hand‐layup technique. The prepared composites were characterized by scanning electron microscopy, thermogravimetry analysis (TGA), flexural, and ablation tests. The C‐Ex composites modified with Zr/Gnps fillers showed significant improvement in thermal stability and flexural strength compared with the pristine sample. The composite containing 0.25 wt% Zr/Gnp filler reduced the mass ablation rate to 23%, whereas back‐surface temperature was decreased to 170°C compared with pure C‐Ex composite. The surface morphology of ablated composite samples revealed that the Zr/Gnp produced char droplet spheres on the carbon fibres, which prevented the further oxidation of the matrix and thus improved the ablative performance.