Investigations in subsurface damage when machining γ′-strengthened nickel-based superalloy

Abstract

γ′-strengthened nickel-based superalloys are developed for high-performance systems such as jet engines, internal combustion engines, and gas turbines. Their excellent properties are given by specifically designed microstructure. Unfortunately, the structure is deformed during machining. Too much deformation generated results in components with low mechanical integrity and reduced in-service life. Experimental investigations indicated that the machining affected zone or subsurface damage formation for nickel-based superalloys is an atypical phenomenon; its dependence on the process parameters is fundamentally different from the conventional materials. This research investigates subsurface damage formation in orthogonal cutting tests performed on nickel-based superalloys, followed by empirical and numerical modeling. The simulations are used to estimate the depth of the subsurface damage and are compared with the experimental results. The knowledge can then be applied to select optimum cutting parameters for an acceptable depth of subsurface damage.