Novel TiAlCN/VCN nanoscale multilayer PVD coatings deposited by the combined high-power impulse magnetron sputtering/unbalanced magnetron sputtering (HIPIMS/UBM) technology

A new TiAlCN/VCN coating combining high hardness, low friction coefficient and chemical inertness has been developed for dry machining of "Sticky" (Al-, Ti- and Ni-based) alloys as well as advanced Metal-Matrix-Composite (MMC) materials used in aerospace and automotive industries. Excellent performance was achieved due to the synergy between V and C as main coating elements and the nanoscale multilayer structure of the coating. TiAlCN/VCN was deposited by the combined High-Power Impulse Magnetron Sputtering/Unbalanced Magnetron sputtering (HIPIMS/UBM) technology. Macroparticle free V+ ion flux generated by HIPIMS discharge was used to sputter clean the substrates prior to the coating deposition. A 0.4 mu m thick TiAlN base layer followed by 3 mu m thick TiAlCN/VCN nanoscale multilayer coating was deposited by unbalanced magnetron sputtering. The sputtering was carried out in a mixed CH4, N-2 and At atmosphere. In dry milling of Al7010-T7651 alloy, TiAlCN/VCN nanoscale multilayer PVD coating outperformed state of the art Diamond Like Carbon (DLC, Cr/WC/a-CH) coating by factor of 4. In drilling Al-alloy enforced MMC materials, cemented carbide drills coated with TiAlCN/VCN produced 130 holes compared to 1-2 holes with uncoated drills. (c) 2008 Elsevier Ltd. All rights reserved.