A Study on Machining Insulating Ceramics with Micro-EDM

• Main Authors: Sheng-Siang Chang, 張勝祥
• Other Authors: Gwo-Lianq Chern
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/98667942048599257915

碩士 === 雲林科技大學 === 機械工程系碩士班 === 96 === In this research, Wire Electrical Discharge Grinding (WEDG) technology was utilized to machine SiC insulating ceramics, and the values of discharge gap, dimensional accuracy of groove, machining velocity of area and surface roughness were also discussed under different parameters. The research was divided into three stages to be proceeded. The initial stage was to assemble and reform the WEDG mechanism, and then to carry out the experiments with varying transmitting velocities of brass wire. The middle stage was to conduct experiments of discharge gap, dimensional accuracy of groove, machining velocity of area and surface roughness by utilizing optimal voltage parameter in the initial stage, and to discuss the effect on SiC insulating ceramics under different parameters. The last stage was to perform experiments of machining micro structure of SiC insulating ceramics by utilizing the optimal parameters of discharge gap, and to discuss the feasibility of machining. From the experimental results, the optimal voltage for best transmitting velocity of brass wire was 8.5V. The machining of SiC insulating ceramics with WEDG could be get carried out under the discharging parameters (Ton of 2μs / I of 0.5A / C of 0pF / Concentration of 0g/L) with minimum discharge gap. The machining efficiency of powder-mixed-EDM (PMEDM) could be highly increased by selecting proper concentration (Al : 1g/L / Gr : 1g/L) but PMEDM damaged the surface roughness. The increasing of pulse duration and current would also increase the surface roughness. To sum up, the micro structure of SiC insulating ceramics could be successfully manufactured by WEDG with micro-EDM.