Development and characterization of polymer–ceramic continuous fiber reinforced functionally graded composites for aerospace application

Functionally graded materials (FGMs) have continuous change in the composition across the thickness which results in gradual change of the properties. The ability of the FGMs to perform more than one contrasting functions as an integral structure makes them an attractive material for aerospace applications. So far the research focus has been on the functionally graded coatings and particulate reinforced functionally graded composites. In this study, continuous fiber reinforced functionally graded composites (FGCs) have been prepared using quartz fabric reinforcement for thermo-structural aerospace application. Silicone resin and fused silica powder have been used to obtain graded matrix. The FGC laminates have been characterized for mechanical and thermal properties. The laminates were also evaluated for thermal shock resistance and thermal insulation properties by exposing to infra-red heating lamps under high heating rate of about 800°C/s and high heat flux of 0.6 Wmm−2 for 70 s. FGC laminates did not de-laminate or charred. Temperature drop across the laminate of 8 mm thickness was found to be 600°C. The concept of FGC fabrication process is demonstrated to fabricate scaled down typical airframe sections also.