Mechanism And Experimental Study Of Electrolyte Flow Field In Small Holes Electrochemical Machining

Electrochemical machining(ECM)is one of non-traditional machining technologies,which is based on the principle of the anodic dissolution.In the machining process,the anode is dissolved by the oxidation reaction,and the dissolved product is carried away by the electrolyte flowing with high velocity and pressure.And finally the anode workpiece is shaped.The surface quality of workpieces by ECM is good,such as there is no cutting stress and thermal deformation on workpieces and the production efficiency is high.In addition,difficult-to-cut materials,complex profiles and alloy parts with high strength and high hardness can be easily be machined.Because in ECM workpiece material is removed in the form of ions,the ECM has the potential to be applied in the micromachining fields.In recently the effect mechanism of electric and electrolyte flow fluid in ECM has been the research focus,especially for small or micro structures.In order to improve the machining precision and stability,the research is mainly on the effect mechanism of the electrolyte flow fluid.Based on the ECM theories,the distributions of the electrolyte flow parameters are compared between the method of adding a certain complexing agent in the electrolyte and the one of disturbing electrolyte with ultrasound.According to the Chemical,the Fluid Mechanics and the analysis software Fluent,the flow velocity and pressure distributions are obtained.In this paper,taking small holes for research objects,the effect mechanism of the electrolyte flow fluid on workpieces’ machining stability and accuracy are respectively analyed.To improve the analysis accuracy of the electrolyte flow fluid,the “dynamic fluid”and “static fluid” are proposed to simulate the flow parameters’ distributions.The cylindrical cathode and the spiral cathode are respectively used to mahining small holes.By comparing anaysis of the electrolyte flowing characteristics,the result is that the machining accuracy with the spiral cathode can be improved.Because there is a velocityvector,which can be helpful in homogenization of the electrolytic parameters distributions.And the influence of the complexing agent added in the electrolyte is discussed.Due to the chemical reaction of the agent and the dissolved products,the solid matter is reduced from the inter-electrode gap.So the distributions of electrolyte flowing parameters are improved and the machining accuracy is improved also.In the paper experiments are developed to ECM small holes.Experimental results show that with the help of agent and ultrasound assisted,the distribution of electrolyte flow fluid are all improved.But the machining stability and accuracy can be more effectively improved in ECM by ultrasonic disturbing electrolyte.And compared with cylindrical cathodes,the use of spiral cathodes is more conducive to small gap electrolytic machining.