Papers by Author: Tibor Szalay

Abstract: The micro electrical discharge machining is a novel technology applicable for the production of geometries which cannot be made by any other technologies assuming the material is electrically conductive. The machining of electrically conductive ceramics becomes possible by this way. Hole machining into these materials has high importance, however the machining parameters for the efficient and acceptable quality manufacturing are still not well discovered. In this paper authors introduce the experiments focused on learning some most important relationship between the composition of the ceramics and the machining efficiency.

Abstract: Nowadays micro hole drilling is more and more applied machining operation. Because of less than 1 millimeter diameter, and of the relatively high thrust force, micro drills are more easily break than conventional ones. In this paper the experiences of micro drilling tests are summarize in order to demonstrate that measuring thrust force is efficient way to recognize the tool breakage. In order to evaluate the micro drill breakage monitoring method the authors carried out experimental measurements varying the cutting conditions, too.

Abstract: The introduced cutting model uses the widely applied mechanical-dynamical differential Lagrange model together with one of the most popular experimental force model (Kienzle-Victor model) in order to provide the more accurate demonstration and simulation of cutting processes. To increase the reliability of the results the authors considered as much parameters and as complex chip geometry as the calculations and processing made it possible. In this paper the sophisticated model of milling operation was the aim of the authors. The simulation results show good equivalency with the measured real cutting experiments. In spite of the complexity of the equations the rapid development in the informatics (hardware and software tools) helped the handling and quick calculation of the equations in this type of models.

Abstract: In this paper a new method for instantaneous cutting force prediction is presented, in case of sculptured surface milling. The method is executed in a highly parallel manner by the general purpose graphics processing unit (GPGPU). As opposed to the accustomed way, the geometric information of the work piece-cutter touching area is gained directly from the multi-dexel representation of the work-piece, which lets us compute the forces in real-time. Furthermore a new procedure is introduced for the determination of the cutting force coefficients on the basis of measured instantaneous or average orthogonal cutting forces. This method can determine the shear and ploughing coefficients even while the cutting geometry is continuously altering, e.g. in the course of multi-axis machining. In this way the cutting forces can be predicted during the machining process without a priori knowledge of the coefficients. The proposed methods are detailed and verified in case of ball-end milling, but the model also enables the applying of general-end cutters.