In-situ synthesis of SiC-ZrB2 coating by a novel pack cementation technique to protect graphite against oxidation

A multiphase coating was prepared on a graphite substrate by a two-step technique to enhance the oxidation protection ability of graphite. The first step was to obtain a functionally graded SiC layer and the second one was to develop a SiC-ZrB2 coating by an in-situ reaction method through a novel pack cementation technique with Zr, Si and B4C powders. The phase compositions, microstructure and element distribution of the coating were...