New mechanistic cutting force model for milling additive manufactured Inconel 718 considering effects of tool wear evolution and actual tool geometry

Abstract

Inconel 718 is widely used in aircraft industry due to its properties. Nevertheless, its mechanical and chemical properties make it hard-to-cut. As a consequence, additive manufacturing is developed in order to get near net shape part before machining. Thus, this article presents a study on the machinability of the Inconel 718 obtained by additive manufacturing compare to one from wrought bar. Firstly, the machinability in milling is investigated through microstructure observation and cutting forces analysis, then a tool wear observations for both material are realised. Thereafter, novel formulations of cutting force model in milling are developed associated to precise treatment and identification process. Thus, the cutting forces are modelled with a mechanistic approach fully parameterized, and furthermore the tool geometry as well as the local forces model consider tool flank wear effect. This study shows that additive manufactured Inconel 718 are the easiest to machine and that considering tool geometry evolution considering tool wear improves the model precision.