Tool wear characteristic of a Binder-less cBN tool in cutting of Bio-titanium alloys

Abstract

A binder-less cBN tool with improved high temperature durability was applied for machining of titanium alloys. The tool exhibited lower extent of flank wear and kept sharper cutting edge compared to the tools made of cemented carbide, sintered cubic boron nitride and polycrystalline diamond with Co-based binder, after machining operation of Ti-6Al-4V alloy under condition in cutting speed of 4.2 m/s with application of high pressure coolant. Using the binder-less cBN tool, the cutting performance for two types of vanadium-free titanium alloys, Ti-6A6-2Nb-1Ta and Ti-15Mo-5Zr-3Al, was investigated. For the former alloy the extent of flank wear was almost equivalent to that for the Ti-6Al-4V alloy with similar mechanical property. The cutting edge of the tool failed in earlier stage for machining of the Ti-15Mo-5Zr-3Al alloy with higher tensile strength than Ti-6Al-4V alloy.