Fabrication of an Electrode Insulation Layer for Electrochemical Machining by Using hot Dip Aluminizing and Micro-arc Oxidation Method

In electrochemical machining, the machining accuracy will be affected by stray current. The most effective improvement is to coat the insulation layer on the electrode sidewall so that current can only be accurately released from the desired area. In this study, the tungsten carbide tool coated by aluminum is performed by the hot dip aluminizing process. Thereafter, which were oxidized by the micro-arc oxidized process to form an aluminum oxide insulating layer to improve extend the life of the electrodes and accurate shape. The electrode is tested in sodium chloride solution and expected to develop a long-life precision electrode with insulation layer for electrochemical machining, reducing the stray electrochemical machining effects to achieve the improving the shape precision of the mold cavity.