Experimental Analysis of Finish Turning of Inconel 617

Abstract

Inconel 617 is a nickel-based superalloy whose properties include corrosion and oxidation resistance in high temperature environments. Due to their material properties, Inconel alloys are commonly used in aerospace applications where resistance to high pressure and temperature is required. These properties also cause the material to be hard to machine due to high temperatures in the cutting zone and its tendency to work harden. This paper focuses on improving the surface integrity and tool life for turning of Inconel 617 for use in next-generation nuclear applications. Various machining parameters are tested to improve the finish and tool life such as the feed rate, cutting speed, and depth of cut. While the machining of popular Inconel grades, such as Inconel 718, have been highly studied and understood, Inconel 617 lacks the knowledge base and research to define how the alloy behaves in machining and how it compares to other grades. Tests on tool coatings confirmed that commercially available coatings are durable enough to withstand the machining of this superalloy in finish turning and determined that AlTiN coatings provide the longest tool life. The investigations performed uncovered the relationship between cutting parameters and their influence on the surface integrity and tool life. MQL deposition was tested and found to be comparable and at times better than conventional flood coolant and may be considered a replacement for coolant after more improvement. This work details the knowledge and experimental procedure used to understand the machining of this superalloy.