Research on micro spiral structure using EDM deposition in air

A new micro electrical discharge machining (EDM) deposition method is presented. The basic principles of micro EDM deposition were analyzed and the realized conditions were predicted. With special electrical parameters, the micro three-dimensional spiral structure was obtained with a brass electrode on an ordinary EDM shaping machine. Through experiments, the effects of electrical parameters and working medium on the micro spiral structure were studied. Results show that the 19-circle micro spiral structure with 0.19 mm in external diameter, 0.1 mm in wire diameter and 3.39 mm in height can be formed on the high-speed steel surface only using the feed of z axis. Measurements show that the micro spiral material has obvious delaminating structure and high corrosion resistance, whose components depend on the tool electrode material although Zn in the electrode is oxidized to ZnO. In addition, the forming of micro spiral structure is discussed through experiments.