| A novel truing and dressing technology on super-abrasive grinding wheel, named surface dry-electrical discharge assisted truing and dressing of non-metal bonded diamond grinding wheel (SDDD), has been proposed in this paper. SDDD process eliminates vast dielectric liquid and produces less corrosion and pollution to function units in contrast EDD. This method widening the application range of EDD, make EDD method can be used to truing and dressing the non-metal bonded diamond grinding wheel, like resin-bonded diamond wheel. In this paper, the mechanism of the selective removal of the bond, as well as wheel surface profiles and topography control technologies of SDDD process have been systematically studied combining methods of theoretical analysis and experimental study. It will have an important theoretical value and practical significance not only for the cost reducing and increasing efficiency but also for the promoting the development and application of SDDD technology on preparation of super-abrasive grinding wheel.In this paper, in order to understand the relationship between discharge and EDM process, impressed air, emulsification oil mirage, water mirage are adopted in this experimental. In this experimental, first, Optical Microscopy (OM) was used to analyses the topography of diamond wheel after truing; Then compared the diamond wheels'truing ratio under different discharge mediums; It is indicated that emulsification oil mirage medium can produce the best ground surface and good truing ratio. Impressed air medium produce the lowest ratio and the worst ground surface, water mirage medium produce the similar truing ratio with emulsification oil mirage medium.Conventional EDD technology shows important limitations that it is only applicable to metal-bonded wheels. In this paper, one of the most important things is proposed novel SDDD technology which can truing and dressing non-metal super-abrasive grinding wheels such as resin-bonded diamond wheel by means of covering electrical material on the surface of wheel. The principle of removing resin bond during SDDD process is illustrated. The thermal and electrical physical properties differences between bonds and diamond abrasives are analyzed. At the same time, the mechanism of removal of the bond and revealing diamond grains has been studied.A series of dressing experiments were carried out on a TROOP434 Die-Sinking Electrical Discharge Machine according the bond removal mechanism and thermal propagation model. The influence of process parameters including discharge current, pulse duration, and discharge voltage on dressing quality was systematically studied with experiments. The condition of the wheel before and after SDDD was analyzed by to find change. Wheel surface topographies before and after dressing was observed by optical microscope (model: KEYENCE VH-800 Digital HD).Truing and dressing the resin-bond diamond wheel by SDDD experiments results indicated that discharge current had direct influence on the wheel surface topography and the performance of diamond grains, the suitable discharge current in SDDD is 1-3A. As well as, the pulse duration had less influence on the wheel surface topography, the suitable pulse duration in SDDD is 10μs-50μs.The discharge voltage had no influence on dressing quality and efficiency. From this, we know the discharge current and pulse duration are the chief parameters which can affect dressing quality. In the same time, the experimental shows the conductive performance of the assisted powder and the servo precision of the feed mechanism had important effects to the surface topography.
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