Optimum electrode path generation for EDM manufacturing of aerospace components

Nowadays the trend of using monolithic parts on aerospace industry has suffered a considerable increase due to the benefits they provide. However, their complex shape and the low machinability of the materials used to manufacture them make their manufacturing by conventional methods difficult or even impossible. Electro discharge machining is an alternative to manufacture this kind of parts. Existing solutions do not offer a generic method that guarantees the smoothness of the erosion path, independently of the workpiece geometry and "user-dependent" features. With the aim to solve the problem, a new objective function has been proposed and a hybrid optimization method (Genetic Algorithm+Trust Region Reflective method) has been implemented. Results obtained by a single variable problem show that the proposed objective function generates a smooth path regardless of machined shape and available degrees of freedom. Therefore, the implemented optimization method combines a low computational cost together with the obtaining of the largest possible electrode. The optimized algorithm has been applied to an industrial case-study, the erosion of a shrouded blisk, to check its adequacy. The lack of instabilities during the erosion of the part proves the best performance of the developed work. An optimized electrode path generation algorithm has been presented.The algorithm can be used to manufacture aerospace components by EDM.An objective function has been proposed to obtain smooth path and stable erosion.The chosen optimization method ensures a large electrode and low computational cost.The developed work has been validated applying it to the erosion of a shrouded blisk.

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