Air Jet Assisted Machining of Titanium Alloy

Abstract

Titanium alloy has been applied to elements and structures in aerospace engineering, bioengineering, marine engineering, etc. because of its superior properties. However, machining of this alloy is likely to accelerate tool wear, shorten tool life and deteriorate the surface integrity. Therefore, high-speed machining of this alloy has been studied for many years. In this study, finish-turning of Ti-6Al-4V was conducted at higher cutting speeds using a new lubrication method called air jet assisted (AJA) machining, in which not only the cutting fluid but also the jet of compressed air was applied to the cutting zone to extend tool life. The results of cutting experiments using an uncoated cemented carbide tool showed that the air jet toward the tool tip applied to the conventional wet machining was effective to extend the tool life. Finally, cooling mechanism in AJA machining was discussed from a viewpoint of enhancement of the heat transfer coefficient from the cutting tool to the cutting fluid.

Keywords

• titanium alloy
• finish turning
• air jet assisted machining
• tool life
• tool wear
• cooling mechanism
• enhancement of heat transfer coefficient