Product Distribution And Parameter Optimization In Pulsating Electrochemical Machining

Pulsating electrochemical machining(ECM)is an important precision method of ECM.Various factors such as flow field,electric field,temperature field,electrolysis product distribution and cathode tool reciprocating vibration will affect the machining process in pulsating ECM.Compared with traditional ECM,it is a more complicated multi-physics coupling problem.In addition,the precise design of the cathode tool is a prerequisite for ECM.The analysis and mastering of pulsating ECM machining is an important basis for cathode tool design.Therefore,the paper has carried out the following researches on the product distribution and parameter optimization in pulsating ECM.(1)Through the multi-physics coupling simulation analysis,the distribution rules and transport characteristics of the electrolysis products such as bubbles and Joule heat in the machining gap are mastered.Multi-physics coupling simulation research is carried out for direct current ECM,pulse ECM and pulsating ECM under different machining gap.The distribution of bubble rate,temperature and current density in ECM under different machining gap were compared and analyzed.The results show that the influence of electrolysis product accumulation on machining gap is significantly reduced in pulsating ECM compared with direct current ECM and pulse ECM.At the same time,the difference in current density along the flow direction is also significantly reduced,which helps to improve the accuracy of ECM.(2)An optimization method based on the uniform distribution of current density along the flow direction is proposed.Parameter optimization between pulse width and pulse interval is performed based on a strategy in which the current density is uniformly distributed along the flow direction and the electrolysis product can completely remove the machining gap in pulse interval.The aim of parameter optimization is that the numerical fluctuation of current density in machining gap is less than 20% and the product completely removed the machining gap.The pulse parameters optimized by pulse ECM and pulsating ECM are obtained.Pulse ECM and pulsating ECM experiments were carried out for the optimized pulse parameters.The results show that the optimized processing parameters can improve the machining accuracy of ECM.(3)Through the observation experiment of current along the flow direction,the distribution rule of current density along the flow direction in direct current ECM,pulse ECM and pulsating ECM under different machining gap is grasped.The simulation results are compared and analyzed.The results show that the distribution of current density along the flow direction is basically consistent with the simulation results,which verifies the reliability of the simulation results.