Process modeling study of the ultrasonic elliptical vibration cutting of Inconel 718

As an advanced cutting method, ultrasonic elliptical vibration cutting (UEVC) has been successfully applied to machine difficult-to-cut materials for the last decade. However, few researches have been studied on cutting of Inconel 718 using a single-point diamond tool applying the UEVC method. The objective of this paper was to experimentally derive empirical equations for the prediction of multiple machined surface roughness parameters for UEVC machined Inconel 718 workpiece by means of a systematic statistical experimental approach. A Taguchi parametric screening design of experiments (DOE) was carried out to systematically determine the UEVC process parameters with the largest effect on mean surface roughness. Next, empirically determined equations for the four common surface roughness metrics (Ra, Rq, Rc, and Rz) were developed via Box-Behnken surface response tests. Validation tests were conducted resulting in predicted and experimental surface roughness in varying levels of agreement. The ultrasonic effect on surface quality was also discussed to confirm feasibility of UEVC of Inconel 718 with diamond cutting tools.