Development Of Pulse Power And Experimental Research Of ELID Grinding Technology

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 precision grinding of hard and brittle materials, many kinds of new grinding methods have been developed. ELID(Electrolytic In-process Dressing)grinding technique is one of the easiest practical application grinding technology. The technique combines the dressing of grinding wheels with the grinding process. In the course of grinding with the minute cutting of grinding wheels, the wheels are also being dressed by the nonlinear electrolysis. Thus, the phenomena of passivation and obstruction are avoided and the precision grinding of hard and brittle materials is achieved. At the same time, it is difficult to truing metal-bonded wheels by conventional methods, so ED truing techique has been developed. This paper first focuses on re-design of the high frequency pulse power for desired performance, then have a study of the technology of ELID grinding with cast-iron bonded diamond wheel and ED Precision Truing of Metal-bonded Grinding Wheel.First of all, this paper introduces the high frequency pulse power for ELID grinding, and makes a big improvement of its performance with an output of high frequency pulse voltage,which established a good foundation for automation technique of ELID precision grinding. Then, ED electro-discharge truing (ED truing) technique is explained in detail. The shape precision of grinding wheel affects the surface finish of work piece directly. But the precise truing of a cast iron bonded grinding wheel is considerably difficult. So the author carries out a series of experiments for spark truing on the base of sparkling processing principles, and at the same time a data collecting system is used to collect the current and voltage. With the help of it, the surface quality can be estimated real time. By means of spark truing, the cast iron bonded diamond grinding wheel can meet the requirements of ultra precision machining. At last, this paper introduces the principle, process, and its characteristic of ELID grinding. The author carries out ELID grinding experiments of Si2N3 material on the MM7120A grinding tool with surface accuracy less than 5nm.