A Comparative Evaluation of Mechanical and Ablative Properties of Ceramic/Phenolic Composites filled with different fillers

Ceramic Fibre Reinforced Polymer composites are attractive materials for various engineering applications, particularly for high temperature application such as a heat shield. In this study, Alumina/Silica based ceramic fibre reinforced phenolic resin composites filled with different fillers such as Yttria-stabilized zirconia, microsilica and cenosphere were prepared using traditional hand layup technique. Three different fillers were filled with phenolic resin in various filler concentrations. Mechanical characterizations such as tensile and compressive were carried out to quantify the effect of fillers on the mechanical properties of the filled composites. An enhancement in mechanical properties of the filled composites was found as concentrations of filler content increased. However, beyond certain concentrations, further addition of the fillers showed a reduction in mechanical properties of the filled composites. Ablation behaviors of the filled composites were investigated by oxyacetylene ablation test in terms of the linear ablation rate, mass ablation rate and back face temperature. Experimental results showed a favorable ablation resistance with the addition of all the micro sized fillers. In comparison with microsilica filled ceramic/phenolic composites, the phenolic matrix embedded with the yttria-stabilized zirconia particles significantly improved the ablative properties of the filled composites in terms of mass ablation rate and linear ablation rate but not when compared to cenosphere filled composites. The result of the mechanical and the ablation characterization of different fillers filled composites were compared and discussed in detail.