Multiphysics research in electrochemical machining of internal spiral hole

Abstract

Electrochemical machining (ECM) is a complex process including the flow field, electric field, and thermal field. The material removal is influenced by the multiphysics. However, the variation of each field is complex. With the development of the CFD, this problem can hopefully be solved. In the present, the multiphase flow model and the coupling multiphysics models were built to predict the variation of the electrolyte velocity, the volume fraction of each phase, temperature, and electric conductivity of electrolyte in the interelectrode during the internal spiral hole machining in ECM. The material removal rate (MRR), decided by the electric conductivity, which is influenced by the multiphysics, was also discussed. Simulation results denote that the flow state of electrolyte has the main effect on the disposal of sludge, rise of the electrolyte temperature, and void fraction of hydrogen reduces the electric conductivity of electrolyte and the MRR is also diminished. Experimental verification of the model using an inhouse-built electrochemical machining system for the internal spiral hole (measuring the height of spiral rib) reveals good correlation with theoretical predictions. The present model could predict the forming of the workpiece in ECM and has values for the real experimentation.