高频群脉冲电化学微小型加工中的反向电流与压力波

Reversed Current and Pressure Wave in High Frequency Group Pulse Electrochemical Micro-machining

针对脉冲电化学加工 ,建立了反向电流和压力波的数学模型 ,提出了高频群脉冲电化学加工方法。结果表明 ,充分发挥反向电流作用的电源频率在 1 0～ 2 4kHz之间 ,压力波频率在 40 0～ 1 333Hz之间。反向电流仅与电极本身有关 ,它决定了高频群脉冲电化学加工的主脉冲频率 ;压力波则除了电极外 ,还与电解质性质和流速、极间间隙和电压等有关 ,它决定了高频群脉冲电化学加工的调制脉冲频率。根据模拟结果设计的实验表明 。

In order to clarify two important phenomena, i.e. the reversed current and the pressure wave in pulse electrochemical machining, this paper presents their mathematical model respectively. The high frequency group pulse electrochemical machining (HGPECM) was put forward according to the model. The simulation results indicate: pulse frequency of the power supply is needed in the range of 10 to 24 kHz in order to obtain better effects of the reversed current, and 400 to 1333 Hz for the pressure wave. The reversed current, which decides the frequency of main pulse, is influenced chiefly by electrochemical properties of the electrode. However, a lot of factors bring about influences on the pressure wave deciding the frequency of modulation pulse besides the electrode, such as the properties and the speed of the electrolyte, the inter-electrode gap, the voltage of power supply and so on in the HGPECM. In addition, the verification experiments show that smaller size of the inter-electrode gap leads to excellent machining precision because of the higher frequency group pulse.