Workpiece Surface Integrity and Tool Life Issues When Turning Inconel 718™ Nickel Based Superalloy

TLDR

Inconel 718, a nickel‑based superalloy widely used in aerospace turbine hot sections, has extensive literature on tool life but limited data on how machining parameters affect workpiece surface integrity. The study aims to deepen knowledge of how cutting parameters influence surface integrity, thereby informing the adoption of new tool materials, geometries, and strategies in aerospace applications. The authors first review existing work on the machinability and surface integrity of turning Inconel 718, then conduct experiments varying tool material, geometry, and cutting parameters to assess their effects.

Abstract

Abstract Inconel 718 is one of a family of nickel-based superalloys which are used extensively in the aerospace industry in the hot sections of gas turbine engines. The literature detailing the effects of varying operating parameters on tool life when machining nickel based superalloys is comprehensive, however, relatively little of this data refers to their effects on machined workpiece surface integrity. Greater knowledge of the effects of operating parameters on surface integrity is critical to the acceptance of new cutting tool materials, tool geometries, and strategies, especially by the aerospace industry. The article initially reviews prior work on the machinability and surface integrity achieved when turning Inconel 718. Following on from this a series of experiments evaluating the effects of varying cutting tool material, geometry, and operating parameters are detailed.