微放電掃描加工多結晶鑽石模穴之放電補償研究

Study on Tool Compensation of Polycrystalline Diamond Micro-Cavities Fabrication by Micro-EDM Scanning Process

孫偉倉(Wei-Chang Sun)

指導教授 ： 許東亞

國立臺北科技大學/機電學院/機電整合研究所/碩士(2009年)

摘要

本文主要探討以微細放電掃描加工(Micro EDM Scanning)技術，加工多結晶鑽石(PCD)模穴之放電補償研究。首先比較不同電極材料與放電回路對於PCD之加工效率，加工結果顯示利用純鎢電極與電阻電容(RC)放電回路，可以很快速的加工PCD微細溝槽。因此，得知利用Micro-EDM Scanning加工PCD時，使用純鎢電極與RC放電回路，加工效率較佳。而將此補償值設定於工研院所開發之微放電系統與EDSCAN(CAM)，成功製作倒平頂金字塔形、凹形半球體以及凸形半球體之PCD微細模穴，且尺寸誤差約為2μm以內。在相同補償參數下，加工模穴材料為超硬合金時，結果顯示，尺寸比預設值大，因超硬合金有利於放電加工，所以補償值小於PCD補償設定，方可完成超硬合金模穴加工。而利用此微細放電掃描加工，配合所設定之放電補償參數，PCD模穴表面粗糙度可達Ra 0.2μm， WC模穴可達Ra 0.122μm。

關鍵字

微細放電掃描加工 ； 多結晶鑽石 ； 放電補償

並列摘要

This article describes a wear compensation research with three-dimensional (3D) micro cavities machining of polycrystalline diamond (PCD) material by means of micro electro-discharge machining (μ-EDM) scanning technology. The μ-EDM machining efficiency of PCD was investigated with different electrode material and discharge circuits. The experimental results show that micro-grooves on PCD are formed rapidly by μ-EDM scanning with tungsten electrode and resistance capacitance (RC) discharge circuit. Moreover, combined with wire electro-discharge grinding (WEDG), micro sphere cavities and complex cavities on PCD are successfully machined by μ-EDM scanning process. The surface roughness of cavities on PCD is as small as Ra 0.2μm and the surface roughness of cavities on WC is as small as Ra 0.122μm by means of μ-EDM scanning process.

並列關鍵字

Micro-EDM Scanning ； Polycrystalline Diamond ； Wear Compensation

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