Friction and wear significantly degrade cutting tools and surface quality of machined parts in high-speed machining. This study examines the Ti‑6Al‑4V/WC‑Co contacts under a range of PV (pressure × velocity) of (160-4000 MPa.m/s) with contacting pressures of 64,110,200 and 320 MPa and sliding speeds of 0.5,1,10 and 20 m/s. These contact conditions are representative of the tool-workpiece and tool-chip contacts when machining titanium alloys by cemented carbide tools. The low-speed tests were carried out on conventional test bench using a pin‑on‑disc configuration, while high‑speed tests were made on a gas-gun device. Friction coefficients, wear measurements, and high‑resolution surface analyses were performed for each condition to analyze the contact between tool and workpiece under a large range of sliding speed and pressure. The results reveal a transition from an adhesive‑dominated wear mechanism at high pressures and low speeds to tribo-oxidative and abrasive mechanisms at elevated sliding speeds. In a large range of contact conditions, a non‑linear dependence of the friction law on contact pressure and sliding velocity parameters was found.
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