Wear Behavior of Multilayer Nanocomposite TiAlSiN/TiSiN/TiAlN Coated Carbide Cutting Tool during Face Milling of Inconel 718 Superalloy

Abstract

The Inconel 718 superalloy is one of the most-used nickel based superalloys in the aerospace industry due to its superior mechanical properties, for instance, high thermal and chemical resistance, and high strength at elevated temperatures. However, the work hardening tendency, low thermal conductivity and high hardness of this superalloy cause early tool wear, leading to the material to be called as a hard-to-cut material. Therefore, deposition of a wear resistant hard coating on carbide cutting tools has a critical importance for longer tool life in milling operations of the Inconel 718 superalloy. In this study, carbide cutting tools were coated with multilayer nanocomposite TiAlSiN/TiSiN/TiAlN coating using the magnetron sputtering technique, and wear behavior of the coated tool was investigated during face milling of the Inconel 718 superalloy under dry conditions. Abrasive and adhesive wear mechanisms were founded as main failure mechanisms. The nanocomposite TiAlSiN/TiSiN/TiAlN coated carbide cutting tool gave better wear resistance, and thus it provided 1.7 times longer tool life and a smoother surface (R-a<0.18 mu m) on the Inconel 718 material than the uncoated one.