Fabrication of AlCrN coatings on WC-Co substrates with diamond films interlayer

Physical vapour deposition (PVD) AlCrN coatings were deposited on the microcrystalline diamond (MCD) and nanocrystalline diamond (NCD) coated WC -Co substrates. The structure, morphologies and frictional characterization of as-fabricated composite coatings were investigated. The surface roughness of MCD coated specimen covering with the AlCrN coating dramatically decreased to similar to 239 nm. The AlCrN/diamond coatings could provide excellent antifriction properties compared to the monolayer AlCrN coating, especially the value of coefficient of friction for AlCrN/NCD coated specimen decreased to similar to 0.23, it was much lower than that of the AlCrN coated specimen with similar to 0.50. The results showed that adopting this method, smooth surfaces for MCD coated samples and high antifriction performance for AlCrN coated samples were obtained simultaneously, which provided a beneficial technology for broadening the application field of AlCrN and diamond coatings.