Fabrication of microgrooves by EDM using a laminated disc electrode consisted of different material foils

Different material tool electrodes exhibit various wear rates in electrical discharge machining (EDM). To make full use of such characteristic, in the present study, different materials disc foils including Cu, Cu-Sn alloy and Sn disc foils were used to construct a laminated disc electrode (LDE) blank, performing EDM to fabricate LDE with stable micro channels on the outer edge surface, and then the LDE was applied in EDM to produce microgrooves on workpieces with the same machining conditions. The wear difference between the single disc foil electrode and the corresponding disc foil in the LDE blank, and the WV-EDM formation of the LDE were studied, respectively. The experimental results show that not all the wear patterns of disc foils in the LDE were equivalent to the single disc foil electrodes due to the protection effect between the foils. This method could effectively fabricate the LDEs with stable micro channels on the outer surfaces. During the WV-EDM process of the LDEs, Cu disc foils with lower wear rates exhibited significant protection and wear resistance effects on the adjacent Cu-Sn alloy disc foils, while the latter provided supportive and stabilized effect in return. Finally, based on the proposed method, the array LDEs composed of Cu disc foils, Cu-Sn alloy disc foils and Sn disc foils were obtained and then used in EDM, the microgroove structures and micro-columnar structures were machined on the surface of titanium alloy.