Laser micro sintering: A new method to generate metal and ceramic parts of high resolution with sub-micrometer powder

Abstract

Laser micro sintering (LMS) was developed by the research group at University of Applied Sciences Mittweida and the associated Laserinstitut Mittelsachsen e.V. as the result of research started in 2001 with a project on the possibility of generating parts by selective laser sintering (SLS) with improved resolution. For the successful generation of solid bodies from various metal powders the technology uses essentially sub-micrometer powders, a cylindrical coating blade and a q-switched solid state laser. The resolution and the surface roughness are by more than one order of magnitude better than those achieved by previous selective laser sinter technologies. Presently the technology shows advancements in selective laser sintering of highly resolved specimens of densely sintered Al₂O₃ and SiC ceramics too.

This paper reports the process mechanism of LMS and its principal differences compared to other SLS methods. A variety of laser micro sintered parts from different metals and the newest results in laser micro sintering of ceramic parts are presented. Material specific behaviour in laser micro sintering is discussed. Also the ability of the method will be shown to generate parts of layer wise different materials (laminate sintering) in one sintering machine.

Keywords:

• laser micro sintering
• selective laser sintering
• sub-micrometer powders
• metals
• tungsten
• alumina
• SiC

Acknowledgements

The research and development of LMS has been and is still supported by Deutsches Bundesministerium für Bildung und Forschung and Bundesministerium für Wirtschaft within the projects No. 16IN0320 ‘Cerapid’ (Innonet), No. 03IP506 ‘Rapid Microtooling mit laserbasierten Verfahren’ (Innoprofile) and No. 03X0033B ‘KONAMI’ (WING). Part of the presented results belong to a project No. 9649/1464 ‘Verfahren zur schnellen Erzeugung von keramischen Zahn-Inlays’ supported by the European fund for regional development (EFRE) 2000-2006 in the course of technology promotion and by funds of the ‘Freistaat Sachsen’.