Effect of Multiwall Carbon Nanotubes on the Ablative Properties of Carbon Fiber-Reinforced Epoxy Matrix Composites

The effect of multiwall carbon nanotubes (MWCNTs) on the thermal and ablative properties of carbon fiber epoxy matrix composites was investigated. Thermochemical and oxidation reactions were found to dominate the ablation mechanism. Shear forces and high temperatures were produced using oxy-acetylene torch. Three types of composites were investigated: (a) carbon fiber epoxy matrix composites, (b) carbon fiber epoxy matrix composite containing 0.2wt% MWCNTs and (c) carbon fiber epoxy matrix composite containing 0.4wt% MWCNTs. Composites containing 0.2wt% MWCNTs showed 5.4% increase in erosion resistance, while composites containing 0.4wt% MWCNTs showed 9.6% increase in erosion resistance compared with carbon fiber epoxy matrix composites. Thermal conductivity increased with the addition of MWCNTs, i.e., 15 and 52% in composites containing 0.2 and 0.4wt% MWCNTs, respectively. Due to the addition of MWCNTs, the increased thermal conductivity of MWCNT-loaded epoxy matrix affected the ablation behavior of carbon fibers and resulted in gradual thinning of carbon fibers.