Study On Electrode Wear And The Law Of Interelectrode Discharge Of Micro-EDM

In micro-hole EDM of titanium alloy,the gap between electrode and workpiece is small because of the small pulse energy of micro-hole EDM.When machining micro-deep holes,it is difficult for the corrosion products to be discharged from the narrow machining gap,which makes the discharge state between electrodes complicated.The electrical parameters restrict and influence each other,and the processing technology is complex,which has a great impact on the quality of micro-hole processing.At the same time,too many corrosion products will increase the probability of secondary discharge,resulting in frequent short circuit discharge,making the processing unstable or even difficult to achieve.In order to improve the processing condition and improve the processing quality,this paper first studies the electrical parameters,and explores the influence of electrical parameters on micro-hole processing.On this basis,the effects of special-shaped electrode processing and electrode shape on micro-hole processing were studied.The experiments of micro-hole processing at different depths were carried out.The effects of processing parameters such as peak voltage,peak current,discharge gap,pulse width and pulse frequency on the electrode wear,processing quality and processing efficiency in the process of micro-hole processing of titanium alloy were studied.In order to further improve the state of EDM,the shape parameters of tool electrodes are studied.A 0.21 mm deep groove electrode and a single-spin deep groove electrode were designed and manufactured.Ti6Al4 V micro-hole processing experiments were carried out with different depth groove electrodes.The experimental results show that the single-spin deep groove electrode can significantly improve the quality of micro-hole processing,reduce the processing time and reduce the electrode wear.When the groove depth is 50% of the diameter,the electrode wear is the smallest,and the groove depth is 60% of the diameter,the micro-hole processing morphology is the best.On the basis of deep groove electrode research,spiral groove electrode was designed and manufactured,and micro-hole processing experiments were carried out.In order to solve the problem of micro-spiral groove electrode processing with low stiffness,micro-EDM electrode end milling with double-guide device was adopted to effectively solve the problem of micro-spiral groove electrode processing.Electrodes with different spiral groove elevation angles and spiral groove depths were used to conduct micro-hole electrical processing experiments.The experimental results show that the screw groove electrode can significantly improve the chip removal problem.The stable processing depth increases obviously,and the better processing quality can be obtained when the spiral groove angle of the electrode is 40 degrees.