Microwave CVD deposition and properties of nano / microcrystalline diamond multilayer coatings on tungsten carbide cutting tools

Micro/Nanocrystalline multilayer diamond coatings (DC) were produced using a microwave plasma-assisted CVD process from CH 4 /H 2 (microcrystalline) and CH 4 /H 2 /N 2 (nanocrystalline) gas mixtures and deposited on common tungsten carbide tools. High resolution surface electron microscopy, Raman spectroscopy, friction, wear and scratching resistance tests were performed to study properties of the four series of DC. It was shown that such multilayer DC not only display good adhesion and wear resistant properties, but also have high surface smoothness and extremely low friction coefficient.