Tool Wear Analysis of Micro End Mills - Uncoated and PVD Coated TiAlN & AlTiN in High Speed Micro Milling of Titanium Alloy - Ti-0.3Mo-0.8Ni

Abstract

Titanium and its alloys are used in many applications like bio-medical, marine, automotive and aerospace. Inorder to achieve desired surface finish without traditional coolants, investigation of micro end mills wear analysis in high speed micro end milling process is essential. Micro end mill performance while machining can be evaluated using cutting force analysis. In this paper tool wear investigation of uncoated & PVD coated AlTiN, TiAlN tungsten carbide end mills in high-speed micro end milling of Titanium Alloy - Grade 12 (Near Alpha) - Ti-0.3Mo-0.8Ni- under dry cutting conditions was presented. The present investigation was also supported by the cutting force analysis. Tool wear observation was done by SEM analysis. EDX analysis was performed to know the material constituents and wear mechanisms on the cutting tool tip. It is found that diffusion, oxidation, adhesive and abrasive wear mechanisms were the major phenomena taking place on the cutting edge of micro end mills. From the comparison of cutting tools for machining Titanium Alloy-Grade 12, it was found that uncoated tools performed better than AlTiN and TiAlN tungsten carbide tools.