Electrochemical etching for micromachining of corrosion resistant alloys

In this paper, basic characteristics of an electrochemical etching of Ni-Fe corrosion resistant alloys (Inconel, Hasteloy, stainless steel) and other Ni-Fe alloys (Permalloy, Kovar) have been studied. All alloys could be electrochemical etched similarly in LiCl-methanol electrolyte. At wide pattern space, etched surface was rough and etched profile became W-shape. However, good etching with mirror like smooth surface could be carried out at narrow pattern for all alloys. Etch rates were about 13mum/min and etch factors were as high as 1.5. The electrochemical etching technique has been applied to not only fine patterning, but also wide pattern etching by connecting of neighboring narrow etched patterns with side etching. The electrochemical etching has been also applied to non-planar micromachining of cylindrical surface of a rod and a pipe of corrosion resistant alloys.