12-06-2012: SLM Solutions introduced the SLM 500 HL metal 3D printer
It was one of the very first equipped with four laser heads.
On December 6, 2012, SLM Solutions unveiled the SLM 500 HL — one of the first metal 3D printers on the market featuring four lasers. The machine had a build chamber measuring 500 x 280 x 325 mm, enabling the production of large components in a single manufacturing cycle.
A key feature of the 3D printer was its configuration of four lasers: two 400 W lasers and two 1000 W lasers, operating within two independent heads. Each of these lasers worked on the same powder bed, significantly increasing the process speed. The use of "dual spot scanning" technology allowed the lasers to operate simultaneously, resulting in productivity up to three times higher compared to single-laser systems.
The SLM 500 HL employed an advanced powder bed fusion method based on two different laser beam profiles — "shell-core imaging." This approach enabled selective melting of the material with different power settings depending on the geometry and layer thickness. The layer thickness ranged from 20 to 200 micrometers, with a scanning speed of up to 15 m/s.
Additionally, the use of a continuous powder transport system eliminated the need for manual material refilling. The process of removing excess powder was also automated and conducted in a specially designed, interchangeable build chamber.
The SLM 500 HL offered a build rate of 70 cm³/h, which was significantly higher than that of SLM Solutions' previous models. Thanks to its four lasers, different areas of the build chamber could be processed simultaneously, reducing the production time for large components. The modern cooling system and interchangeable build platform allowed the next production cycle to start without waiting for the previous print to cool down, further enhancing the device's efficiency.
The SLM 500 HL is still in production, though now referred to more commonly as the SLM 500. SLM Solutions has enhanced the system over time, including updates to its laser configurations and software. It remains one of their flagship machines for high-performance metal additive manufacturing, known for its four-laser setup and automated powder handling system.
Source: www.3ders.org