An investigation on the cutting performance of nano-crystalline diamond coatings on a micro-end mill

In conventional milling, appropriate coatings can be used on tools to enhance their cutting performance and efficiency of the production process. In an effort to improve the tooling performance in micro-scale milling, nano-crystalline diamond films were applied on a micro-end mill by a hot filament chemical vapour deposition process. The cutting performance of the nano-crystalline diamond-coated tool, including cutting forces, tool integrity, surface roughness and burr formation, were evaluated in slot milling of aluminium 6061-T6 against that of an uncoated tool in dry cutting conditions. Reduced cutting forces, free chip adhesion, lower tool wear, improved surface roughness, as well as smaller burrs, were observed using the nano-crystalline diamond-coated tool. The investigation illustrates the possibility of applying nano-crystalline diamond coatings on micro-milling tools for dry cutting and better tooling performance.