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Precision tools with structural resolution reaching the 20 micrometer range can be generated on an industrial scale by "laser micro sintering". Components featuring aspect ratios above 12 and a roughness R a down to 1.5 micrometers have already been produced from sub micrometer grained metal powders. The components can be generated either firmly attached to a substrate or fixed in an easily separable mode. If supporting structures are employed, undercuts up to 90° are feasible, without, a process parameter dependent maximum angles of undercut below 90° are obtained. The process has been introduced into the market, labeled microSINTERING by 3D-Micromac AG.

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As mechanical engineering industry encounters a growing demand of µ m-sized or µmstructured components and tools for an increasing range of applications, miniaturization is presently ranking among the most important goals in product and tool development. Compared to still higher resolving techniques, selective laser sintering (SLS) still bears the advantages of relatively low production costs and short processing times for uniques as well as small series productions of micro parts. Prismatic or tapered microstructures can be applied as electrodes for electro erosion, as tools for direct shaping of plastic materials or as molds for injection molding. Furthermore freeform-meaning "tool-independent"-undercuts and hollows can be realized, allowing e.g. the fabrication of miniature tools and components with hydrodynamic functions. Therefore SLS remains an attractive tool for the mentioned size range. Until recently commercial SLS units with a laser focus diameter of 40-500µ m were unable to generate metal micro parts smaller than 100µ m. The Laser Institut Mittelsachsen e.V (LIM) in Mittweida, Germany, has developed a procedure and a device, which makes feasible the selective laser sintering of solid and structured parts out of metals and in the future ceramics. The obtained structures show a resolution of less than 30 µ m for overall resolution. Contingent on the parameters, the generated bodies are either firmly attached to the substrate or can be dissevered by a non-destructive method. The technique has been successfully applied to produce functional micro tools or micro-components for tools from powders of refractory as well as lower melting metals in steps of 1µ m thick sintered layers.