Wear Mechanisms of New Tool Materials for Ti-6AI-4V High Performance Machining

Nowadays, Ti-6AI-4V turning is mastered for cutting speed lower than 60 m/min by using carbide and high-speed steel tools. At higher cutting speed, chemical and mechanical properties of Ti-6AI-4V cause complex wear mechanisms such as adhesion and diffusion. Thus, to machine over 100 m/min without using high-pressure cooling, new tool materials need to be tested and their behaviour understood. This paper presents the interactions between polycrystalline diamond (PCD), cubic crystalline boron nitride (CBN), and TiB2 coated carbide with titanium based alloy. The different wear patterns are not only strongly linked to the chemical reactions, but also to the different phase changes, which occur with PCD and CBN tools.