微细群电极的电火花超声复合反拷加工技术

Reverse Copying Technology for Micro-electrode Array Fabrication by Ultrasonic Enhanced Micro-EDM

针对LIGA制作微细群电极工艺复杂、价格昂贵的缺点,提出微细群电极的电火花超声复合反拷加工技术.根据微细电火花放电的机理,利用微细群孔放电反拷来制作微细群电极.基于微细群电极反拷电加工时圆柱电极不能旋转的特点,在加工中复合了超声振动,并在理论分析的基础上,系统地研究超声振动对微细群电极反拷电加工的影响.得到一系列3×3的微细群电极和由这些群电极制作的微细群孔,单电极直径小于30μm,长径比大于10,表面光洁,有很好的同轴度.

This paper presented a reverse copying technology for micro-electrode array fabrication by ultrasonic enhanced micro-EDM, for micro-electrode array fabrication by LIGA has shortcomings such as complex technology and high price. Based on the mechanism of micro-EDM, micro-hole array discharge is used to fabricate micro-electrode array by reverse copying. In the process of reverse copying, the thicker rod electrode can not rotate and results in electric arc and short-circuit easily, so the process is enhanced by ultrasonic vibration. The influence of ultrasonic vibration is analyzed theoretically and proved by machining experiments. Finally, 3 × 3 arrays of microelectrode and micro-hole array made with these micro-electrode arrays are obtained, the diameter of a single electrode is less than 30 μm and the aspect of the holes ratios is more than 10, also they have good surface quality.