A comparative study of the tribological behaviour of PVD coatings on the Ti-6Al-4V alloy

• Published in: Tribology international Vol. 44; no. 3; pp. 297 - 308
• Main Authors: Martini, C., Ceschini, L.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-03-2011; Elsevier
• Subjects: Applied sciences; Chromium nitride; Coatings; Dry sliding; Drying; Exact sciences and technology; Friction, wear, lubrication; Machine components; Mechanical engineering. Machine design; Modulus of elasticity; Multilayers; Physical vapor deposition; PVD coating; Ti-6Al-4V; Titanium base alloys; Tribology; Tribometers; Ti-6Al-4V; Dry sliding; PVD coating; Tungsten carbide; Multilayer coating; Deformation modulus; Chromium nitride; Multiple layer; Metal; Alloy-Ti90Al6V4; Titanium base alloys; Dry friction; Tribological coatings; Composite coating; Friction coefficient; Physical vapor deposition; Friction test; Sliding friction; Tribology
• ISSN: 0301-679X; 1879-2464
• DOI: 10.1016/j.triboint.2010.10.031

This work focuses on the tribological behaviour of PVD coated Ti-6Al-4V. Commercially available single layer CrN, CrN/NbN superlattice and multilayer WC/C coatings were taken into consideration. The dry sliding behaviour of the coated systems was studied by a flat-on-cylinder tribometer (load range 30–60
N). A critical load, corresponding to the end of coating life, was identified for each coated system. The highest critical loads were observed for CrN- and WC/C-coated Ti-6Al-4V. However, only WC/C also led to a significant decrease of the coefficient of friction. The good performance of WC/C-coated Ti-6Al-4V was ascribed to both the high
H/
E ratio of the coating and to the best match of elastic modulus with the substrate.
► Evaluation of dry sliding behaviour of CrN, CrN/NbN and WC/C-coated Ti-6Al-4V. ► All the PVD coatings improved the wear resistance of the Ti-6Al-4V alloy. ► Critical load identified for each coated system: highest for CrN and WC/C. ► Only multilayer WC/C coating improved wear resistance and decreased friction.