SURFACE QUALITY OF THE EDM PROCESSED MATERIALS
The article presents the importance of the EDM technology in the industry of machine building. It is mostly used in the machining of stamps and special processes in which the conventional technologies are inefficiently. It's known that only condition of machining with this method is that the material should be electro conductive. The main parameters that are followed during the process are the precision and the roughness of the surface. The collective tried to emphasise the importance variation of the roughness concerning some machining parameters. Some of the measurements were conducted at ETH Zurich using an electronic microscope.
Critical assessment and numerical comparison of electro-thermal models in EDM
Abstract Several modeling approaches have been attempted to characterize the electrical discharge machining (EDM) process based on electro-thermal concepts. However, each model has varied characteristics and approximation results. It is important to elucidate the differences of each model and their proximity to the real material removal process. In this paper, five EDM models from Snoeys, Van Dijck, Beck, Jilani, and DiBitonto are analyzed in terms of the temperature distribution, crater geometry, and material removal at the cathode. Comparative analyses on the material removal rate (MRR) ratio of the predicted result to experimental data for discharge energy range from 0.33 to 952 mJ showed that DiBitonto's model yielded the closest proximity of 1.2–46.1 MRR ratio. This is followed by Jilani (2–45.9 MRR ratio), Snoey (3.9–203.2 MRR ratio), Beck (4.9–197.7 MRR ratio), and Van Dijck (26.8–1399 MRR ratio). This paper also shows that the disk heat source models can be enhanced by improving the approximation of the heat flux and energy fraction.
Determining the Jaw Relationship
Contacts between the upper and lower posterior teeth of complete dentures take place during the opening and closing strokes of mastication (Brudvik and Howell 1990). These contacts are fast, gliding impacts of the mandibular teeth which contact close to the position of maximal intercuspation of the teeth, called the “intercuspal occlusion”. The intercuspal position is the position adopted by the mandible when the teeth are in intercuspal occlusion.