Working Principle of Selective Laser Sintering (SLS)

Selective Laser Sintering is a powder-bed additive manufacturing process in which a laser selectively heats regions of a powder layer so that particles fuse together.

Working steps

1. A thin layer of polymer, metal or other suitable powder is spread uniformly over the build platform.
2. A laser scans the cross-sectional areas defined by the sliced CAD model.
3. The laser supplies sufficient energy to sinter or fuse the selected powder particles.
4. The build platform moves downward by approximately one layer thickness.
5. A new layer of powder is spread over the previous layer.
6. The laser again scans the required cross-section and bonds it to the previous layer.
7. Steps 4–6 are repeated until the complete part is produced.
8. After printing, the part is allowed to cool and is removed from the surrounding loose powder.
9. Excess powder is brushed, blown or otherwise removed; additional post-processing may be performed.

Important features

• Loose surrounding powder can provide support for many geometries, reducing the need for dedicated support structures.
• Part quality depends on powder properties, laser power, scan speed, layer thickness, hatch spacing and bed temperature.

Result: A three-dimensional component is obtained by selectively fusing successive powder layers according to the digital model.