Fabrico de peças por microsinterização laser

Microparts by a Novel Modification of Selective Laser Sintering
Peter Regenfuss, Lars Hartwig, Sascha Klötzer, Robby Ebert, Horst Exner
Authors are with Laserinstitut Mittelsachsen e.V. at the University of Applied Sciences Mittweida, Technikumplatz 17, 09648 Mittweida, Germany, email: [e-mail]

Keywords: Freeforms, Micro Structures, Nanopowders, Selective Laser Sintering, SLS, Tungsten.

Abstract: Microparts with a structural resolution of 10 have been generated by selective laser sintering. The technique includes sintering under conditions of vacuum or reduced shield gas pressures. A novel set-up and raking procedure is employed; the material is processed by a 1064nm Nd-YAG laser. The procedure allows the work pieces to be generated from powders of high melting metals like tungsten as well as lower melting metals like aluminium and copper. Contingent on the parameters, the generated bodies are either firmly attached to the substrate or can be dissevered by a non-destructive method. The set-up is equipped with a device suited to rake thin layers of sub-micrometer grain sized powders as well as slurries; it also fulfils the requirements for selective reaction sintering and selective laser sintering of ceramics

1. Introduction: Selective laser sintering (SLS), a familiar technique in rapid prototyping and rapid tooling, was heretofore preferentially applied for the generation of macroscopic freeforms. Commercial devices with a laser focus diameter of 40-500µm still do not allow generation of microparts smaller than 100µm. Therefore since its first application, efforts have not ceased to increase the resolving power of SLS, aiming for dimensions in the range of 20µm. This is beyond the bounds of classical chip removing or milling processes. Compared to still higher resolving techniques, SLS sintering still bears the advantages of relatively low production costs and short processing times for uniques or small sample numbers. Prismatic or tapered