Research on the machining characteristics of vertical ultrasonic vibration assisted WEDM-LS

Abstract

ABSTRACT In this paper, a novel composite process technology – Low Speed Wire Electrical Discharge Machining (WEDM-LS) with Vertical Ultrasonic Vibration (VUV) assisted is put forward to improve the performance of traditional WEDM-LS. First, a fluid-solid coupling model of interelectrode flow field and workpiece is established. The simulation result reveals that under the assistance of Vertical Ultrasonic Vibration of workpiece, the velocity of deionized water near the wall of discharge craters is much higher than traditional WEDM-LS or WEDM-LS with the assistance of wire ultrasonic vibration (Wire USV). Therefore, Vertical Ultrasonic Vibration is helpful to the removal of residual debris from the craters. Second, the multiphase flow model of debris, deionized water, and bubbles between electrodes was constituted, and it shows that workpiece vibration frequency is positively correlated with the movement intensity of bubbles and debris, which promotes debris removal throughout the whole processing area. Finally, based on the Taguchi method, the experiments of traditional WEDM-LS, Wire USV assisted WEDM-LS and VUV assisted WEDM-LS were conducted. The workpiece was selected as TiNi-01 shape memory alloy (SMA). The experimental results reveal that under the large electrical machining parameters, Vertical Ultrasonic Vibration assisted WEDM-LS can achieve excellent machining efficiency and quality.