Graphics Reference
In-Depth Information
Metals
Meanwhile in Texas the first steps were taken in developing an AM technique that could
also use metal as well as plastic, ceramics and glass. In a project initiated by Dr. Carl Deck-
ard, a group of researchers from University of Texas developed the Selective Laser Sintering
(SLS) technique in the middle of the 80s. The team incorporated DTM in 1989. DTM in its
turn was bought together with the rights to the SLS technology by 3D systems in 2001.
Metal manufacturing with DTM's SLS is an indirect method since metal powder first is bon-
ded together with polymer to create a brittle “green” part. Then the polymer is burned away
in a kiln-like oven, and finally the part is infiltrated with molten bronze. In the same time
another technology that would take the lead in AM metal production was developed on the
other side of the Atlantic by the pioneer of 3D printing in Europe: EOS.
The German company Electro Optical Systems (EOS) was founded in 1989. In 1994 EOS
developed Direct Metal Laser Sintering (DMLS) (as well as polymer laser sintering). DMLS
was the first method to melt and fuse the metal powder directly with a laser beam with no
use of post-processing. As always in 3D printing development, material was a big concern.
The first DMLS process used a bronze and nickel based powder. In the latter part of the 90s
steel powder was introduced.
In 1995 another project in Germany initiated by the Fraunhofer Institute for Laser Techno-
logy (ILT) led to a technology called Selective Laser Melting (SLM). This technology took
DMLS further by enabling the production of fully dense parts by melting single compon-
ent (i.e. one single metal) materials. The ILT project saw a lot of spin-offs. The company
Fockele & Schwarze (F&S) founded by two laser researchers with the same names who
were involved in the project, first took advantage of it by commercializing and naming the
SLM technology, although the original patent belonged to ILT. The SLM technology then
saw several company transitions. In 2000 F&S entered into a partnership with MCP HEK
Gmbh. In 2004 Dr. Fockele founded Realizer Gmbh while Dr. Schwarze continued with
MCP HEK Gmbh which changed name to MTT technologies in 2008. MTT technologies
was then divided into an English branch and a German branch which was renamed SLM
Solutions Gmbh in 2010. The English branch was bought by the British company Renishaw
in 2011.
Another German company, Trumpf, was also involved in the project with ILT in 1995.
Trumpf, which specialized in laser technology, cooperated with the US company Precision
Optical Manufacturing - POM Group Inc. (currently DM3D Technology) in launching Dir-
ect Metal Deposition (DMD) machinery in 2003. This technology was developed by the
University of Michigan around 1995 and then commercialized by POM (DM3D) which
