Experimental Research On ELID Ultra Precision Grinding And ED Precision Truing Of Metal-bonded Grinding Wheel

With the development of science and technology, the hard and brittle materials,such as ceramics are meeting a wider adoption. In order to realize the ultra precisiongrinding of hard and brittle materials, many kinds of new grinding methods have beendeveloped. ELID (Electrolytic In-process Dressing)grinding technique is one of theeasiest practical application grinding technology. The technique combines the dressingof grinding wheels with the grinding process. In the course of grinding with theminute cutting of grinding wheels, the wheels are also being dressed by the nonlinearelectrolysis. Thus, the phenomena of passivation and obstruction are avoided and theprecision grinding of hard and brittle materials is achieved. At the same time, it isdifficult to truing metal-bonded wheels by conventional methods, so ED truingtechique has been developed. This paper focuses on the technology of ELID grindingwith cast-iron bonded diamond wheel and ED Precision Truing of Metal-bondedGrinding Wheel.First of all, this paper introduces the data acquisition system based on graphicprogramming language LabVIEW. The system that can real-time display, record andanalyze all kinds of experimental signals is the research means and foundation ofspark truing technique and ELID precision grinding technique. Then, EDelectro-discharge truing (ED truing) technique is explained in detail. The shapeprecision of grinding wheel affects the surface finish of work piece directly. But theprecise truing of a cast iron bonded grinding wheel is considerably difficult. So theauthor carries out a series of experiments for spark truing on the base of sparklingprocessing principles, and at the same time a data collecting system is used to collectthe current and voltage. With the help of it, the surface quality can be estimated realtime. By means of spark truing, the cast iron bonded diamond grinding wheel canmeet the requirements of ultra precision machining. At last, this paper introduces theprinciple, process, and its characteristic of ELID grinding. The author carries outELID grinding experiments of Si2N3 material by self-developed ELID grindingequipment on the MM7120 grinding tool, promotes ELID principle and methods'development and realizes Si2N3 material ultra precision grinding of the surfaceaccuracy less than 50nm.