| Summary: | 博士 === 大同大學 === 機械工程研究所 === 89 === ABSTRACT
In this dissertation, Micro machining of EDM process was studied for processing different difficulty-to-cut materials with tungsten carbide electrode. A batch production technique was proposed to machine micro multi-electrodes, numbers of micro-holes, and micro slots could be processed in a time.
Performance of special material on different machining parameter was studied; a mathematic model for EDM process was regression with business soft well “AIM”. Neural network model was also developed. Performance can be effectively predicted through developed neural network from known parameters. Basic EDM knowledge was obtained from these experiments. Performance of semi-conductor BaTiO3 was studied next. Simple genetic algorithm was used to search optimum parameters for smallest surface roughness.
Micro machining by EDM process were investigated on conventional EDM machine then. First part was to study on micro-EDM drilling, after comparison and analyzing the electrodes between copper and tungsten carbide, tungsten carbide was selected as electrode to process copper and stainless plate. Experimental results revealed that high quality micro-hole could be achieved by positive polarity machining with tungsten carbide electrode on conventional EDM machine.
Second part of dissertation was the study of micro slots. A thin electrode was used to cut slots on conventional CNC EDM machine; material is removed in a depth until desired thickness was finished. This is so-called EDM milling. For a transverse slot, if electrode can be processed; fabrication time can be served up to two third.
Third part was the study of micro slot of trajectory. Results revealed that micro slots of 2 dimensional trajectory could be processed on conventional CNC EDM machine.
Last part is study of batch production method. High quality of micro parts can be fabricated through micro EDM process. The shortage of micro EDM is which can’t become a batch production method. For example, to drilling the micro holes, a developed electrode rotating mechanism was used to process the multi-electrodes. Comparison with single electrode, electrode processed time of 36 pieces of multi electrodes is one eleventh of single electrode. Processed time of workpiece is one seventh. The more of micro holes, the much of time served. Cost of fabrications can be decreased effectively by proposed batch production of EDM with multi-electrodes. Principle of this method can used in multi-slots, micro punching, laser machining.
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