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this transition from prototype production to serial
(low-volume) production. The DMRC is the result
of the merging of eight companies and research
institutes, and receives financial support
from the government of North Rhine-Westphalia.
The four founding companies—Evonik, Boeing,
EOS and MTT Technologies—will invest a total of
€ 2 million in the DMRC over the five-year contract
period. Since the opening of the DMRC in
May 2009, the participating experts have focused
mainly on practical questions, such as man aging
the temperature of the machines being used or
the long-term properties of sintered parts.
While a good, substantive idea for a new technology
can come into being quite suddenly, it may
still have difficulty reaching the heads of key players.
This is true in the case of additive manufacturing.
Many universities teach the conditions for
“freedom of design” and “function-driven design“
inadequately, if at all. While engineers receive intensive
training in conventional processes, they
usually learn very little about freedom of design,
which opens the door for them to additive manufacturing.
Indeed, additive manufacturing is based
on the idea of fundamentally different design,
since the designer must think in terms of complete
functionalities and not decoupled component
parts.
Standards as pathbreakers
Lack of training at the universities is not the only
hurdle. In the past, development, modification
and use of mold-free production processes was
quite unsystematic. This is why there are currently
no standards to promote widespread use of the
process and regulate evaluation of existing products.
As a result, part testing yields different values
for elasticity module, tensile strength and elongation,
for example, depending on the set of param
eters used (Fig. 5). Both the ISO and ASTM,
however, are working on developing the first
standards for laser sintering. ISO 27547-1 is already
in force for the production of test bodies. VDI is
also drafting guidelines.
Despite the hurdles and unanswered questions
that still exist, the importance of AM will grow
appreciably over the next ten years. The advantages
outweigh these problems: developers can
produce functional hollow structures in small
batches, and the structures can be precisely modified
to changing stress requirements. The components
can be customized with specific porosities
or surfaces, and ultra-lightweight components are
also possible. Here, the airline industry is one of
the pioneers. There are already about 30 SLSsintered
components installed in the Boeing 787.
elements32 evonik science newsletter
D e S i G n i n G w i t H P o l Y M e r S
Figure 4. Comparison of the technical properties of a part produced by
laser sintering and one produced by injection molding
Test method Laser sintered Injection molded
test bar test bar
Density g/cm³ DIN 53479 0.95 1.04
E modulus MPa DIN 53457 1,700 1,400
Tensile strength MPa DIN 53455 48 46
Elongation % DIN 53455 18 >50
Figure 5. Depending on the parameter set, tests on the same part can yield differing
values and make evaluation more difficult. Standards should improve this situation
Test method Parameter Parameter Parameter
set 1 set 2 set 1,
upright built
Density g/cm³ 0.91 0.9 0.91
Modulus of elasticity MPa DIN 53457 1,872 1,920 1,921
Tensile strength MPa DIN 53455 49 48 49
Elongation % DIN 53455 18,2 8,4 7
According to estimates by Airbus Industries, an
aircraft produced entirely through additive manufacturing
would be 30 percent lighter and 60 percent
more cost-effective than current machines.
Resources and energy efficiency—combined
with economical production—are the central challenges
of the future for Germany, if it intends to
remain competitive in a fast-changing world. In
the past, it was often the work of people that think
outside the box and therefore helped breathe life
into a new technology. They also play a role in additive
manufacturing. One thing is certain: sooner
or later, additive manufacturing technologies will
become key players in placing advanced industrial
production on a cost- and resource-efficient footing.
l
SyLVIA MONSHEIMER
Born in 1965
Sylvia Monsheimer is responsible for
global market development of additive
manufacturing for evonik’s High
Performance Polymers Business line.
Previously, she managed the business
line’s Strategic innovation Projects department.
Monsheim came to evonik
in 1989 after receiving her degree in
construction engineering. Since then,
she has held a wide variety of positions
in application engineering for high performance polymers. Her
more than ten­year focus on powder development and application
engineering for selective laser sintering and other tool­free processes
is a hallmark of her work at High Performance Polymers.
+49 2365 49-5911, sylvia.monsheimer@evonik.com
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