Research On Compound Machining By Ablation Discharge And Grinding Based On Sintered Diamond Electrode

At present stage,electrical discharge machining(EDM)is used to the material that is difficult to cut.But the EDM method is subject to the energy of the pulse power,and the efficiency is very low.Spark induced ablation is a new method for materials difficult to cut.The electric spark induces activation of the pmachining area.Then the combustion reaction between oxygen and activation area achieves the purpose of removing the material,and the efficiency greatly improves.But the oxidation products attached to the surface of the workpiece has an influence on subsequent discharge which affected the machining efficiency.Therefore,this paper proposes the sintered diamond electrode(SD-electrode).The diamond particles scrape the oxidation layer which promotes the continuous and efficient ablation.Specific works were as follows:(1)This paper proposed compound machining by ablation discharge and grinding based on sintered diamond electrode and designed a complete experimental platform.At the present stage,the ablation discharge produced many oxidation layer which attached the machining area.Its resistivity was high and it was not easy to burn.The substrate of the SD-electrode participated in the machining of ablation discharge.At the same time,the diamond particles scrape oxidation layer which ensures high machining efficiency.(2)This psper put forward a servo control method based on pressure signal and conducted three methods.The system consisted of pressure acquisition,signal processing and servo driven.It also included the real-time acquisition and data monitoring based on LabVIEW.This paper also proposed three control methods and conducted comparative experiment.(3)This paper studied on the characteristics of the compound machining of ablation discharge and grinding and set up machining model.The whole reaction process was divided into four parts.They were discharge induction,high efficiency ablation,abrasive grinding and electrode dressing.(4)This paper carried on the process optimization research.It studied the parameter on the machining characteristics.The machining efficiency of compound machining was 6.3 times that of the inner jetted dielectric EDM.The machining efficiency increased by 88% compared with that of the aerosol ablation.This paper conducted the contrast experiment of high strength steel.The efficiency of compound machining is 1.3 times of atomization ablation,and the surface quality of composite machining is better than that of atomization ablation.