By: Khai Pham Xuan, Kazuya Saginawa, Rie Tanabe, Yoshiro Ito
Department of Mechanical Engineering, Nagaoka University of Technology
Recently, high precision molds for small products are being highly required in many industrial applications, especially in information communication technology. Mold materials with high hardness, such like cemented tungsten carbide (WC-Co), are difficult to machine by classical chip-removal techniques and the electrical discharge machining (EDM) is mainly used technology in microfabrication of hard materials. Even though the accuracy of EDM is fairly high K.H. Ho and S.T. Newmann, State of the art electrical discharge machining (EDM), it has several drawbacks such as slow machining rate and the additional time and cost needed for polishing and finishing processes. Recently, laser machining becomes an effective technique for machining of hard materials. Many experimental results show that short pulse laser machining allows removal of very small amount of material with little heat affected zone compared with nanosecond or longer pulse lasers.