The Technology Study Of EDM-induced Ablation Machining In Aerosol Dielectric

EDM-induced ablation machining (EDM-IAM) in aerosol dielectric is a new way to remove thematerials. The intermittent high-pressure oxygen exhausted from the electrode reacts with theactivated metal produced by spark in the gap. The material removal rate is greatly enhanced by usingthe chemical energy produced by the metal combustion. The ablation energy distribution is unevenly,and the workpiece burns easily. Based on the discharge dielectric which is made of aerosol generatedby oxygen and water, experiment on forming by spark-induced combustion is done. The main work ofthis paper is as follows:1. Set up the test system and choose the appropriate atomizing nozzle based on designrequirements and objectives of EDM-IAM in aerosol dielectric.2. A preliminary study on the mechanism of EDM-IAM in aerosol dielectric is carried out byanalyzing machining wave form, surface micro-morphology. The "tandem discharge" feature ofdroplet between electrodes and the dispersion effect of combustion energy affected by droplets inspark-induced combustion are researched.3. The experiment is compared with s EDM-IAM in pure oxygen dielectric and inner jetteddielectric EDM. The material removal rate (MRR) of combustion in aerosol dielectric is improvedclosely20﹪than pure oxygen, and4.6times higher than jetted dielectric. The relative tool wear ratio(TWR) decreases65%compared with EDM in jetted dielectric. Its forming accuracy is also high. Andthe edges rounding radius reduces nearly35%compared with EDM in jetted dielectric.4. Technological rule research is carried out in this paper. The result shows that the materialremoval rate will be changed as electrical parameters and the pressure of the gas and liquid, but therelative electrode wear rate keeps at a very low level. Use Fluent to simulate and analysis the flowfield in gap.5. The jetted liquid and atomization ablation is a process which uses the aerosol generated byoxygen and water as the discharge dielectric to improve the material removal rate. In the stage of nooxygen, the oxide layer covering ablation surface is trimmed by EDM of inner jetted dielectric. Theexperiment is done about deep holes machining.