Machinability investigation of Inconel 718 in high-speed turning

Superalloy Inconel 718 is widely used for many industrial applications due to its unique properties. However, machinability of the material is considered to be poor due to its inherent characteristics. The machinability studies of Inconel 718 had been carried out by earlier researchers mostly at low or medium cutting speed. Machinability indices used in such cases have the characteristics such as cutting force, surface roughness, cutting temperature, etc. In the case of high-speed machining of Inconel 718, machinability indices such as chip compression ratio ( ζ ), shear angle ( Ф ), surface integrity, and chip analysis are of prime importance. Most of the researchers have not given due consideration to these vital machinability indices necessary for understanding of high-speed cutting of Inconel 718. In this work, an experimental investigation was carried out to understand the behavior of superalloy Inconel 718 when machined with cemented tungsten carbide (K20) insert tool. The result and analysis of this work indicated that the above-mentioned machinability indices are important and necessary to assess the machinability of Inconel 718 material effectively during high-speed machining.