Grooving on SiC Ceramics Surface by Reaction with Solid Metal (Part 2)

Chemical reaction between SiC ceramics and Ni or Fe foil has been used for making grooves on the sliding face of SiC ceramics. To accomplish the grooving process, the grooved face of SiC ceramics should be crack free and smooth. The reaction product layer between SiC ceramics and Ni foil was composed of deposited graphite, δ-Ni2Si and Ni3Si2. Generation of cracks in SiC ceramics was not dependent on the product species, but dependent on the size of deposited graphite. Larger graphite grains more deteriorated reaction layers, and generation of cracks in SiC ceramics was prevented. Reaction between SiC ceramics and Fe foil yielded graphite, Fe5Si3 and Fe3Si. Extended reaction vanished Fe3Si and generated no cracks in SiC ceramics. The thickness of SiC ceramics consumed was calculated from the thickness of Ni or Fe foil and the product species and was shown to coincide with the observed value.