An Investigation of the Effect of Novel Mono/Bi-Layered PVD-Coated WC Tools on the Machinability of Ti-5Al-5V-5Mo-3Cr

• Published in: Materials Vol. 17; no. 15; p. 3743
• Main Authors: Syed, Hasan S., DePaiva, Jose M., Saciotto, Victor, Veldhuis, Stephen C.
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.08.2024
• Subjects: Alloys; Bilayers; Comparative analysis; Computer software industry; Cutting force; Cutting tools; Deformation; Diamond machining; Diamond tools; High speed machining; Industrial applications; Liu E; Machinability; Machining; Mechanical properties; Monolayers; Surface properties; Surface roughness; Temperature; Titanium alloys; Titanium base alloys; Tool life; Tribology; Tungsten carbide; Turning (machining); Workpieces; United States; United Kingdom; United States > US; machinability; AlCrN; PVD coatings; Ti-5553; tribology; cutting tool
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17153743

The Ti-5Al-5V-5Mo-3Cr (Ti-5553) alloy is a relatively novel difficult-to-cut material with limited machinability and tool life analysis available in the literature, and hence requires further investigation. This study focuses on the machining and tribological performance of Ti-5553 under high-speed finish turning (150 m/min, 175 m/min, and 200 m/min) via novel mono/bi-layered PVD-coated WC tools. A base AlTiN coating is used as the reference monolayer coating, with AlCrN, diamond-like ta-C, and TiAlSiN coatings each deposited on top of a base AlTiN coating, totaling four separate coated tools (one monolayer and three bi-layer). Tool life, cutting forces, workpiece surface quality, and tribological chip analysis are among the subjects of investigation in this study. Overall, the AlTiN/AlCrN coated tool outperformed all the other combinations: an improvement of ~19% in terms of tool life in reference to the base AlTiN coating when averaging across the three speeds; lowest surface roughness values: ~0.30, 0.33, and 0.64 µm; as well as the lowest chip back surface roughness values: ~0.80, 0.68, and 0.81 µm at 150, 175, and 200 m/min, respectively. These results indicate that the AlTiN/AlCrN coating is an excellent candidate for industrial applications involving high-speed machining of Ti-5553.