A Novel Approach for Batch Production of Micro Holes by Micro EDM

S. T. Chen(a), Y. S. Liao(b)
a: Department of Mechatronic Technology, NTNU, No. 162, He-ping East Rd., Sec. 1, Taipei, 106, Republic of China
b: Department of Mechanical Engineering, NTU, No. 1, Roosevelt Rd., Sec. 4, Taipei, 106, Republic of China

Abstract

The paper proposed a novel approach of effective production of mass micro holes. A set of micro w-EDM mechanism is designed and mounted on the developed tabletop precision machine tool. The tension of micro wire is precisely controlled by magnetic force. In addition, the micro vibrations of the wire during discharging are effectively suppressed by the developed vibration suppression system. In order to fabricate the mass micro holes, the microstructure array of the high aspect ratio 10×10 micro squared electrodes with the width and the height of 21μm and 700μm, respectively for each electrode, and the spacing between two electrodes of 24μm is fabricated first by the proposed “reverse w-EDM” machining strategy. This micro electrodes array is employed directly to machine the mass micro holes on the same machine via the modified micro EDM peck drilling. By sequentially positioning the micro electrodes array after one drilling through process, the 900 same size micro through-holes array is successfully obtained on the stainless steel board of 0.1mm thickness. The results show satisfactory hole geometry, dimensional accuracy and surface roughness. More, it is verified that the mass micro holes can be fabricated efficiently by the proposed approach.