Selective Laser Melting

Selective Laser Melting (SLM) is a well established AM technology to produce metal parts. In the SLM process, metal powder is melted by the energy of a laser beam. The part is built layer by layer. After the laser has melted one layer a new layer of powder is added to the resulting work piece. Then the laser is used again and melts the next layer.
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Processing characteristics

The key characteristics of the SLM process can affect the material selection, the component design and the final application:

  • High cooling rates in the range of 10'000 – 100'000 °C/s can lead to problems with the processing of conventional alloys, but allow also to achieve novel microstructures and to process novel alloy compositions.
  • The material must be available as powder with the right grain size and morphology.
  • The amount of powder for a build job is determined by the sample height; High components require a large amount of powder
  • Several part geometries need additional support structures, which will have to be removed from the part afterwards

Materials

  • Commercially availabel : Stainless steel (1.4404), aluminium alloys (AlSi10), titanium alloys (TiAl6V4, Ti Grade 2), Nickel alloys (In 718, In 625), Co-Cr alloys
  • Research: Metal-matrix-composites, structural intermetallic alloys, high temperature alloys

SLM Maschines at Empa

Empa operates in the Coating Competence Center two commercially available SLM machines from renowned machine manufacturers: 

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Concept Laser m2 cusing
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