Tool life and wear mechanisms in high speed machining of Ti–6Al–4V alloy with PCD tools under various coolant pressures

TLDR

Titanium alloys are widely used in aerospace, yet machining them remains challenging, and few studies have examined ultra‑hard tool performance under high‑speed conditions. The study aims to evaluate how high‑pressure coolant affects the performance of PCD tools machining Ti–6Al–4V at high speed. The authors examined tool performance and wear mechanisms under varying tribological conditions during high‑speed machining of Ti–6Al–4V with PCD tools. Higher coolant pressure extends tool life and reduces adhesion, while adhesion and attrition remain the primary wear mechanisms under the tested cutting conditions.

Abstract

Usage of titanium alloys has increased since the past 50 years despite difficulties encountered during machining. Many studies involving different tool materials, cutting parameters, tool geometry and cutting fluids when machining this important aerospace material have been published. However, there are relatively few literatures available on the application of ultra hard tools in the machining of titanium-alloys. The primary objective of this study is to investigate the behaviour of Polycrystalline Diamond (PCD) tools when machining Ti–6Al–4V alloy at high speed conditions using high pressure coolant supplies. Tool performance under different tribological conditions and the dominant wear mechanisms were investigated. Increase in coolant pressure tends to improve tool life and reduce the adhesion tendency, accelerated by the susceptibility of titanium alloy to gall during machining. Adhesion and attrition are the dominant wear mechanisms when machining at the cutting conditions investigated.