Adjustment of wire vibrations in order to improve geometric accuracy and surface roughness at wedm

Abstract

Although WEDM is one of the most precise finishing technologies, deviations from the required geometric shapes and surface roughness occur in the production of parts with rotary sur-faces. Even though these shortcomings have only a minimal impact on planar cuts, the production of circular profiles is a different problem. One of the factors causing this poor quality is the vibration of the wire electrode. With appropriate vibration adjustment, it would be possible to achieve significant improvements of the eroded area quality, both in terms of geometric accuracy and in terms of surface roughness. This would significantly increase quality, enabling WEDM technology to compete with other technologies in terms of economic efficiency. Therefore, the proposed solution aims to provide a partial adjustment to the wire tool electrode vibrations, based on their sensing by the means of acoustic emissions or a laser beam, with subsequent dynamic adjustment of the actual technological parameter values. This way, the given solution will increase the production accuracy of circular holes, increase productivity, and ultimately provide an overall increase in the economic efficiency of the WEDM process. The article also presents the scheme of a control algorithm for monitoring and subsequent adjustments of the vibrations of the wire tool electrode during the electroerosion process in order to minimize geometric deviations of circularity, cylindricity and roughness of the machined surface.