ON INFLUENCE OF WORKPIECE GEOMETRY AT HYDRAULIC MECHANICAL REMOVAL MECHANISM OF ULTRASONICALLY AIDED EDM FINISHING
The paper deals with finite element modelling (FEM) of material removal mechanism due to ultrasonically induced cavitation in the working gap at finishing modes of electrical discharge machining. The influence of some workpiece geometries (shape and dimensions) was studied from the point of view of the optimum value of ultrasonic pressure exerted by shock waves produced by cumulative microjets stage, aiming at obtaining a decrease of machined surface roughness at electrical discharge machining finishing aided by ultrasonics (EDM+US). This is in strong correlation with the consumed power on ultrasonic chain, a key-parameter of working finishing mode. By its appropriate adjustment, the surface roughness at EDM+US can be reduced with almost 50% against that from classic EDM. All these technological issues were supported by FEM results.
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