Mechanical anisotropy and deformation, fracture mechanisms of vertically aligned carbon nanotube arrays/silicon carbide composites

Abstract

A novel vertically aligned carbon nanotube/dense SiC (VACNT/SiC) composite was fabricated by cyclic precursor infiltration and pyrolysis technique. It exhibits ultrahigh Young's modulus, hardness and compressive strength thanks to the dense microstructure, which surpass the values ever reported in literature. The VACNT/SiC composite is always stronger at 0° loading direction than at 90° direction with respect to CNT orientation due to the stronger axial property of individual CNT, despite that different deformation mechanisms were demonstrated at the two loading directions. Specifically, interfacial debonding occurred during fracture of the VACNT/SiC composite, which suggests a weak bonding nature of the VACNT/SiC interface.