Preparation and properties of the composites characterized by grading SiC coatings and graphite substrates

The composites with SiC coatings and graphite substrates are discussed in this paper. Microstructure observations by SEM (Scanning Electron Microscope) and optical microscopes indicate the grading distribution of SiC coating. The thickness of SiC coatings and the distribution of SiC particles have a significant dependence on the reaction temperatures at which the coatings were formed. Test results show that the composites are of high density, high mechanical strength and low porosity, and the excellent performance of oxidation resistance at high temperatures up to 1200degC as well. (author)