Laser Scribing of Stainless Steel with and without Work Media

By: Anna Unt, Heidi Piili, Marika Hirvimäki, Matti Manninen, Antti Salminen

Lappeenranta University of Technology, Laser Processing Technology Research Group, Finland
Machine Technology Centre Turku Ltd, Finland

Improving control and decreasing energy needs have been the most addressed problems of chemical industry in recent years. One of the thoroughly researched options has been bringing down the scale of production units. Productivity comparable with large-scale industrial mechanisms can be reached by grouping simultaneously working milli-scale production units with volumes of few ml/min having reaction channels with length of 1-100 mm, width of 0.5-2 mm and depth of 0.25-2 mm. The use of milliscale devices has been limited due to the lack of cost-efficient production method, manufacturing such channels by laser can give savings on cost and simplify the production cycle.

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Micro-Hole Drilling on Cemented Tungsten Carbide by Ultra Short Laser Pulses

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.

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