الفهرس | Only 14 pages are availabe for public view |
Abstract The electrical discharge machining (E. D. M) process has found ready applications in the machining of hard metals or alloys which cannot be machined easily by conventional methods. It plays a major role in the machining of dies, tools, etc . , made of tungsten carbides, satellites or hard steels. Moreover, alloys used in the aeronotics his process has also the capability of machining complicated components. According to the industry , for example, hastalloy, nimonic, etc. , could be machined by this process .This process has also the capability of machining complicated components. According to the very importance of E. D. M process in industry, various theories have been advanced to formulate its precise mechanism by which metal removal is occurred. The theory which is now generally accepted is called ”the thermal theory” in which the metal removal is assmed to be due entirely to the very high temperature of the spark. from this regard. This work introduced a view to explain the mechanism of metal removal for the (E. D. M) process. This view gives a great importance to the chemical structure of the dielectric flui molecules. The experimental work in this thesis has confirmed the previous statement where it is found that, as the dielectric fluid was complicated in its structure as the machining characteristics improved (metal removal) rate is increased and relative tool wear is decreased. |