Effect of ultrasonic vibration on finished quality in ultrasonic vibration assisted micromilling of Inconel718

Inconel718 was machined with the traditional micromilling (TMM) and ultrasonic vibration assisted micromilling (UVAMM) with the different technology parameters, whose surface quality and burrs formation were studied. The results show that TMM often forms pits, bumps and gullies in the size effect range. UVAMM effectively improves the surface quality compared with TMM. The surface defects are significantly reduced with the increase of feed per tooth (ƒ_z). When ƒ_z exceeds 4 μm, the effect of ultrasonic vibration on the surface quality is no longer obvious. The minimum burr size on the down milling side and the up milling side are 50.23 μm and 36.57 μm, respectively. The feasibility of vibration cutting in improving surface quality and suppressing burr size was verified. UVAMM effectively suppresses the formation of built-up edge, which can significantly improve the micromilling process. The cutting force is obtained through simulation and experiment. They are agreement in the change trend. The finite element simulation can be used to predict the cutting force. Compared with TMM, feeding force (F_x), radial force (F_y) and axial force (F_z) of UVAMM decrease by 7.6%, 11.5% and 1.3%, respectively.