Study Of Precision Electrochemical Machining Technology

In view of the current situation that the traditional DC / pulse electrochemical machining is difficult to discharge the electrolytic products and heat during the small gap machining,precision electrochemical machining technology was invented.cathode vibration and pulse power synchronization match during the processing,Electrolytic corrosion in the small gap,electrolyte flushing when the large gap.Thus improving the physical and chemical process characteristics,improve the processing accuracy and surface quality.At present,one of the reasons that restrict the further development of PECM technology is the lack of an effective simulation model to analyze the machining process.The PECM process involves the electric field,the flow field,the temperature field and the geometric deformation field.It is very difficult to analyze the influence of each field parameter on the final anode surface.Therefore,this subject mainly establishes multi-field coupled simulation model under vibration condition.Through the dynamic simulation to master its basic theory and influence law,which will provide a theoretical basis for the optimization of cathode design and parameters in practical processing.Based on COMSOL Multiphsics finite element simulation platform,a flow field simulation model combining wall function method with turbulence model was established.Aiming at the non-convergence of calculation caused by the reversal of the cathode boundary element under the vibration condition,The free-splitting quadrilateral and the free-splitting triangles were used to mix the processing zones.The effects of cathodic vibration on flow field parameters were obtained by transient simulation of flow field.Meanwhile,the velocity distribution obtained by multi-step steady state flow field was contrasted with the transient solution.Based on the analysis of each physical field,the coupled model of temperature field of PECM was established based on voltage model,and the variation law of temperature in unit cycle was explored.Aimed at the problem of transient calculation of flow field,a multi-step steady-state flow field solution and a cyclic iterative solution algorithm based on COMSOL are proposed and the error analysis is carried out.The results show that this method can greatly reduce the computational time.The error is guaranteed within a reasonable range.The effects of various process parameters on the temperature distribution of the gap between the electrodes were analyzed by iterative method.In order to solve the problem of multi-time scale iteration and parametric iteration,COMSOL with MATLAB is used to simulate the entire machining process.The COMSOL automatic cycle calculation is realized by script modification.Meanwhile,the effects of various process parameters on the removal of anode materials were analyzed.