Tribological, Tribocorrosion and Wear Mechanism Studies of TaZrN Coatings Deposited by Magnetron Sputtering on TiAlV Alloy

• Main Authors: Ernesto García, Martín Flores, Eduardo Rodríguez, Laura P. Rivera, Enrique Camps, Stephen Muhl
• Format: Article
• Language: English
• Published: MDPI AG 2018-08-01
• Series: Coatings
• Subjects: wear mechanism; hard coatings; TaZrN; Ti6Al4V; wear analysis; Raman spectroscopy
• Online Access: http://www.mdpi.com/2079-6412/8/9/295

Different works have demonstrated that tantalum, zirconium, and their nitrides present good biocompatibility. Additionally, TaN and ZrN possess excellent corrosion and wear resistance. Ternary nitrides such as TiAlN have been improved in terms of their mechanical properties with respect to binary systems. Therefore, ternary nitrides as TaZrN have high potential to be used in biomedical applications. This work was focused on studying the tribological and tribocorrosion performance of a TaZrN film. The coating was deposited by DC (Direct Current) magnetron sputtering in a reactive atmosphere using Ta and Zr targets. The tribological characterization was carried out in dry (atmospheric condition) and corrosive environments (synthetic body fluid). The coated surface shows better wear resistance than the uncoated in both conditions. The wear mechanism was studied by FE-SEM (Field Emission-Scanning Electron Microscopy) and Raman confocal microscopy. The wear rate of the coated surfaces was higher in corrosive ambient than in dry conditions. The observed wear mechanism was adhesive–abrasive for lower loads and abrasive at dry conditions for an applied load of 2 N. For corrosive media the principal wear mechanism for 2 N was abrasive–corrosive. For all tests at dry conditions, the formation of a tribolayer of metal oxides, graphite, and amorphous carbon was seen.