工件振动辅助管电极电解加工方孔仿真与试验研究

Simulation and Experimental Research on Workpiece Vibration-Assisted Electrochemical Machining of Square Holes With Tube Electrode

为解决管电极电解加工方孔过程中因流场分布不均造成加工质量差等问题,提出一种工件振动辅助管电极电解加工方孔的方法。流场仿真结果表明,工件振动辅助电解加工能够在加工间隙内不同位置产生明显的脉动流场,改善加工间隙内的电解液流动状态,有效消除传统电解加工方孔中加工间隙内存在的“死水”区,从而有利于电解产物的排出,提升电解加工的稳定性。同时开展试验研究,结果表明,采用工件振动辅助管电极电解加工可以提升方孔加工的轮廓精度和表面质量,并且采用脉冲电流可以进一步提升方孔的加工质量。最终采用振幅0.04 mm、振频20Hz、脉冲占空比80%、脉冲频率5000 Hz、进给速度1.5 mm/min,加工出平均宽度1.218 mm、宽度标准偏差0.026 mm、侧壁表面粗糙度0.703μm的方孔。

In order to solve the problem of poor processing quality caused by uneven distribution of flow field during the process of square holes by electrochemical machining(ECM)with tube electrode,a method of workpiece vibration-assisted ECM of square holes with tube electrode is proposed.The results of flow field simulation indicate that workpiece vibration-assisted ECM can generate obvious pulsating flow fields at different positions within the machining gap,improve the electrolyte flow state within the machining gap and effectively eliminate the stagnant water area within the machining gap in the traditional ECM of square holes,thus facilitating the discharge of electrolytic products and improving the stability of ECM.The experimental researches were also conducted at the same time,and the results show that the use of workpiece vibration-assisted ECM with tube electrode can improve the contour accuracy and surface quality of square holes machining,and the use of pulse current can further improve the quality of square holes machining.Finally,a square hole with an average width of 1.218 mm,width standard deviation of 0.026 mm,side-wall surface roughness of 0.703μm was electrochemically machined by using the amplitude of 0.04 mm,the vibration frequency of 20 Hz,the pulse duty cycle of 80%,the pulse frequency of 5000 Hz and the feed speed of 1.5 mm/min.