Abstract
Low-frequency vibration cutting (VC) is a machining technology wherein a tool periodically vibrates to break cutting chips. However, VC produces tool paths that include air cuts to break up chips, which deteriorates surface roughness and roundness. This study aims to address these limitations. Low-frequency vibrations are applied to both the upper and lower turrets of a multitasking lathe. To improve surface roughness with simultaneous VC, this study presents a theoretical method to calculate the optimal values for frequency and amplitude of VC and the starting positions of the Z-axis of two upper and lower turrets. Simulations and actual machining experiments were conducted after adjusting VC frequency and amplitude and the starting positions of Z-axis of both turrets. Results show that the surface roughness improves with two-turret simultaneous VC compared to one-turret single VC in stainless steel and brass machining experiments, while succeeding in breaking up cutting chips. Furthermore, the surface roughness of simultaneous VC is improved to a level close to that of single and simultaneous conventional cutting (CC) results in stainless steel. Although there is some variation in material, the roundness of simultaneous VC is generally improved compared to single VC and CC. For the machining of brass, the roundness results of the simultaneous VC were better than those of single CC, VC, and simultaneous CC.
