الفهرس | Only 14 pages are availabe for public view |
Abstract The process of electrical discharge machining (EDM) is one of the modern machining processes. That machining is convenient for stiff and high strength parts. Deep drilling, machining inclined surfaces and small-scaled machining are the other applications of this process. Despite the unique applications of this method of machining, high materials removal rate (MRR), low surface roughness (SR), low tool wear rate (TWR). In this study, it was concentrated on the creation of curved hole using a proper mechanism as holes are mostly machined by traditional operations like drilling which is just a combination of straight holes. So a new mechanism technique was designed, which consists of a squared curved electrode holder, a half ball head (electrode) from copper, an arm and a free arm holder to do it with the electrical discharge machining, which is settled on an electrical discharge machine (EDM). from the experimental results, the new designed mechanism could help in creating a curved hole with any inlet distances (X), outlet distances(Y) and also any hole’ diameters as it is just by putting in our considerations each of the length of the arm and the ball’s electrode diameter and by changing them it would be easy to get any desirable (X ad Y) depending on the application, as what already done to make the curved holes with different arc lengths for X and Y = 50, 100, and 150 millimeters and afterwards it was selected arc length for X and Y = 50 millimeters to study some different parameters to get the best case in each test to be used during the process. So, the largest MRR happened when using the current with (30 amperes), (500 µs) pulse ON and (4 µs) pulse OFF. The smallest TWR happened when using the current with (6 amperes), (300 µs) pulse ON and (3 µs pulse) OFF. The smallest surface roughness happened when using the current with (6 amperes), (100 µs) pulse ON and (1 µs pulse) OFF. |