Application of micro-EDM combined with high-frequency dither grinding to micro-hole machining
- 作者：Hung Sung Liu ; Biing Hwa Yan ; Chien Liang Chen and Fuang Yuan Huang
- 关键词：Micro-EDM ; High-nickel alloy ; HFDG ; WEDG ; Micro hole
- 刊名：International Journal of Machine Tools and Manufacture
- 出版年：2006
- 期刊代码：84_08906955
- 类别：et
- 出版时间：2006
- 卷：46
- 期：1
- 页码：80-87
- 文件大小：638 K
摘要
This research presents a novel process using micro electro-discharge machining (micro-EDM) combined with high-frequency dither grinding (HFDG) to improve the surface roughness of micro-holes. Micro-EDM is a well-established machining option for manufacturing geometrically complex small parts (diameter under 100 μm) of hard or super-tough materials. However, micro-EDM causes the recast layer formed on the machined surface to become covered with discharge craters and micro-cracks, resulting in poor surface quality. This affects the diameter of the micro-hole machined and undermines seriously the precision of the geometric shape. The proposed method that combines micro-EDM process with HFDG is applied to machining high-nickel alloy. As observed in SEM photographs and surface roughness measurement, HFDG method can reduce surface roughness from 2.12 to 0.85 μm Rmax with micro-cracks eliminated. Our results demonstrated that micro-holes fabricated by micro-EDM at peak current 500 mA followed by HFDG at 40 V can achieve precise shape and good surface quality after 6–8 min of lapping.