Preparation and Characterization of SiO2/Carbon Foam and SIC/Carbon Foam Composites

The synthesis and characterization of carbon foam supported silica aerogel (SiO2/Carbon foam) and silicon carbide composite (SiC/Carbon foam) are presented in this study. The phase composition, microstructure, thermal and mechanical properties are investigated by XRD, SEM, LFA Laser Flashmeasurements, and Universal Material Testing.The resulting SiO2/Carbon foam composite shows a higher compressive strength (14.95 MPa) and a smaller thermal conductivity (0.44 W .m(-1).K-1) at room temperature, in comparison with the pristine carbon foam. The SiC/Carbon foam composite maintains a compressive strength of 14.66 MPa, and possesses a low high-temperature thermal conductivity (2.18 W.m(-1).K-1 at 1 200 degrees C). Mass loss does not begin until 610 degrees C for the SiC/Carbon foam composite, and complete carbon combustion does not occur until 844 degrees C, indicating a much better thermal stability than the pristine carbon foam in oxidizing atmosphere.