Wire Electro Discharge Machining Process Research Articles

Multi-objective optimization of wire-electro discharge machining process by Non-Dominated Sorting Genetic Algorithm

Wire-electro discharge machining (Wire-EDM or WEDM) is one of the important non-traditional machining processes, which is used for machining of difficult-to-machine materials and intricate profiles. Being a complex process, it is very difficult to determine optimal parameters for improving cutting performance. Cutting velocity and surface finish are most important output parameters, which decide the cutting performance. There is no single optimal combination of cutting parameters, as their influences on the cutting velocity and the surface finish are quite the opposite. In the present work, a multiple regression model is used to represent relationship between input and output variables and a multi-objective optimization method based on a Non-Dominated Sorting Genetic Algorithm (NSGA) is used to optimize Wire-EDM process. A non-dominated solution set has been obtained and reported.

A computer-aided system for the optimization of the accuracy of the wire electro-discharge machining process

The wire electro-discharge machining process (WEDM) has become very popular in the tool-making industry, in which complex geometries with tight tolerances must be generated on difficult-to-machine materials. However, the requirements of accuracy imposed on the process by the users are growing day after day, and therefore strategies for the improvement of the precision must be developed. In this work, a hybrid computer-integrated system for the improvement of the accuracy of corner cutting that combines experimental knowledge of the process and numerical simulation is described. Based on a technological database and a user-friendly interface, the system allows the user to select the optimum cutting strategy, either by wire path modification (when productivity is the main concern) or by cutting regime modification (when high accuracy is required). Simulation supports the decision-taking process by reducing the cost and time-consuming experimental trials. The validity of the system has been tested through a series of case studies, which show the improvements in accuracy and productivity with respect to the commonly used strategies.

Simulation of a micro-computer-controlled robotic hand for wire electro-discharge machining applications

Wire electro-discharge machining (WEDM) is a relatively new machining process with distinct advantages over conventional milling and other metal-removal processes. The production of complex and intricate shapes can be aided greatly, with additional manipulation facilities for the workpiece and/or the cutting tool. For smaller bore dies, an initial circular hole may be machined easily by laser or by traditional drilling methods. The difficulty arises when an attempt is made to machine this initial hole to match a non-circular shape which may contain splines in 3-dimensional space. Currently WEDM machines with an integral control system are available commercially. However, these machines are very expensive, some costing around one hundred thousand pounds, even though they have limited specimen-manipulation facility. The availability of a micro-computer controlled specimen manipulator with greater versatility that is independent of the machine itself would be advantageous and such a manipulator would be significantly cheaper. The present paper describes briefly the design and interfacing of such a manipulator, in particular, the problems encountered during this research work. The incorporation of additional facilities that are essential for the development of this manipulator as an industrial unit are described in detail. Tests have been carried out using a model material to simulate the WEDM process, and components having 3-dimensional external or internal surfaces have been machined.