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special feature
EPMA adopts Additive
Manufacturing and
launches specialist
group at Gothenburg
The European Additive Manufacturing Group was formed
by the EPMA in May 2013; however, PM2013 in Gothenburg
was its first public gathering. Consultant Editor Ken
Brookes reports on the Special Interest Seminar and the
progress being made in this exciting area.
I
n 2013 a relatively new manufacturing technique jumped into the
public domain, attracting notice
with inexpensive home-operated
apparatus for making toys, games and
household objects, even car spares,
and spectacular ‘breakthrough’ objects
from fully-working guns to the ‘Queen’s
Baton’ promoting the Commonwealth
Games. Blessed with a variety of names,
the general public seem to have seized
upon ‘3D manufacturing’ as a generic,
whilst professional industry prefers
‘Additive Manufacturing’.
Among the further subdivisions are
those describing the form and composition of the input material – whether
powder, wire, tube or rod, and whether
metallic or non-metallic. Amateurs
often employ plastic rod or tube for
input, whilst metallic powders are
increasingly preferred as manufacturing
or operational temperatures are raised,
or specifications become more onerous.
Figure 1 illustrates the current place of
additive manufacturing in the spectrum
of PM manufacturing choices. 2014
should be a particularly interesting year,
when some of the key patents on laser
sintering will expire.
The explosion in affordable additive
production (mostly of plastics but also
some low-melting-point metals), has
energised the inventive-names industry,
my current favourite being MakerBot
Industries’ ‘Thing-O-Matic’. A few
more are shown in Figure 2.
At the European Powder Metallurgy
Association’s PM2013 Conference in
Gothenburg, we had to wait for the last
morning and a Special Interest Seminar
to hear from the EPMA’s new Additive
Manufacturing Group and the surprising progress made in recent years.
EAMG
By necessarily restricting their interests
to production utilising raw materials in
metallic powder form, both the EPMA
and Metal Powder Report focus on the
Additive manufacturing positioning
Part
weight
... is complementary to other
PM net shape technologies
HIP
Additive
manufacturing
selective laser melting (SLM)
selective laser sintering (SLS)
electron beam melting (EBM)
laser metal deposition (LMD)
Press & Sintering
MIM
!pma.com
Nb.of parts
Figure 1: Additive manufacturing positioning.
26
rapid prototyping
rapid manufacturing
3D printing
MPR November/December 2013
additive fabrication,
additive processes,
additive techniques,
additive layer manufacturing (ALM)
layer manufacturing
freeform fabrication (FFF)
solid freeform fabrication (SFF)
ADDITIVE MANUFACTURING
Figure 2: Terminological classification of AM.
0026-0657/13 ©2013 Elsevier Ltd. All rights reserved
Figure 3: Co-chairman and presenter Claus
Aumund-Kopp of Fraunhofer Institut,
Germany. (Copyright © Kenneth JA Brookes
2013)
Figure 4: Co-chairman and presenter Ralf
Carlström, general manager of Höganäs
Digital Metal, Sweden. (Copyright © Kenneth
JA Brookes 2013)
most difficult area of AM. Recent rapid
developments created the need for a
specialist EPMA group, not only as a
forum to exchange ideas and techniques
but also to promote the industry and
the ever-widening scope of its products.
The European Additive
Manufacturing Group was launched in
May 2013, but PM2013 in Gothenburg
was its first public appearance. It has
two co-chairmen, Claus AumundKopp (Figure 3) of Fraunhofer IFAM,
Germany, and Ralf Carlström (Figure 4)
of Höganäs Digital Metal, Sweden.
Other members of the steering group
(Figure 5) are Olivier Coube (EPMA
Technical Director), Keith Murray,
Sandvik Osprey, UK (standardisation)
and Adeline Riou, Erasteel, France
(promotion and events). Membership is
open to all EPMA members.
EAMG objectives include the
following:
• To increase awareness of Additive
Manufacturing technology, with a
special focus on metal powder-based
products.
• To gain the benefits of joint
action, for example through
research ­programmes, workshops,
­benchmarking and exchange of
knowledge.
• To improve the understanding of
the benefits of metal-based AM
technology by end users, designers,
mechanical engineers, metallurgists
and students.
Figure 5: EAMG Steering Group. (Copyright © Kenneth JA Brookes 2013)
Table 1: EAMG activities: calendar of events
Dates
Event
Country
Sept 18
EuroPM – SIS on AM Sweden
Sept 19
3DP.SE
Sweden
Sept 19-20
RM Forum 2013
Italy
Sept 25-26
TCT Show
UK
Oct 7-8
AMSI
India
Oct 30-Nov 1
RAPDASA 2013
South Africa
Dec 3-6
Euromold 2013
Germany
Feb 6
EAMG meeting
Germany
March 12-13
DDMC Fraunhofer
Germany
April 6-10
AMUG 2014
USA
May 14-15
Rapidtech
Germany
May 18-22
World PM
USA
June 9-10
Rapid 2014
USA
June
AEPR
France
July 8-9 AM
Conference
UK
Sept 21 24
EuroPM
Austria
metal-powder.net
City
Gothenburg
Kista
Milan
Birmingham
Bangalore
Golden Gate Park
Frankfurt
Frankfurt Airport
Berlin
Tucson
Erfurt
Orlando
Detroit
Paris
Loughborough
Salzburg
Link
www.epma.com
http://3dp.se/
www.eriseventi.com/
www.tctshow.com/
www.amsi.org.in/
www.rapdasa.org
www.euromold.com/
www.epma.com
www.ddmc-fraunhofer.de/
www.additivemanufacturingusersgroup.com/
www.rapidtech.de/en/homepage
www.mpif.org
www.rapid.sme.org
www.afpr.asso.fr
www.am-conference.com
www.epma.com
November/December 2013 MPR
27
months beginning with the Gothenburg
launch event. The Orlando conference
in May 2014 could be especially interesting, as it will parallel the World PM
Congress taking place at the same venue
and dates, with the same organiser.
The next EAMG meeting takes
place at Frankfurt Airport, Germany.
Contact for those interested in attending is Olivier Coube, EPMA Technical
Director, at [email protected].
Sign-off from the group is “Welcome
to the new world of AddiCtive
Manufacturing!”
Seminar
Figure 6: Additive Manufacturing
Technology: an introductory 4 page
­illustrated leaflet from EAMG.
• To assist in the development of
international standards for the AM
Sector.
• The first tangible action of the
EAMG was the production of
an excellent introductory leaflet
(Figure 6), with contributions from
14 EAMG members. It’s available in
print and online, at www.epma.com,
and I strongly recommend it.
By no means fully comprehensive,
Table 1 lists some of the additive
­manufacturing events to be attended or
supported by EAMG members in the 12
The Special Interest Seminar on
State of the Art and Emerging
Markets for Additive Manufacturing
(Figure 7) occupied the final half-day
of the EPMA’s 2013 Conference in
Gothenburg. In addition to Adeline
Riou’s introduction to the new AM
Group, several papers were presented.
Though not published in the official
Conference Proceedings, between them
they covered the subject of additive
manufacturing in great style, though of
course only for metal powder products.
I noted some of their facts and figures.
R & D on Metal Based Additive
Manufacturing, Claus Aumund-Kopp of
Fraunhofer, Germany.
In his presentation, Aumund-Kopp
provided an overview of current
research and development trends in
metallic powder-based AM processes. He included examples of specific
research projects and described their
needs in terms of data handling and
other aspects. Fraunhofer is deeply
involved in this area, with both laser
and electron-beam melting facilities for
current research on aluminium, steel,
Inconel and other metals. Seven companies were included on the list of AM
equipment suppliers.
The presenter described how dental restorations were being produced
by AM at a rate of 2000 a night at a
single location, 500 on each of four
machines. Building ‘envelopes’ (maximum unit volume in terms of length,
width and height) were continually
being increased. New techniques,
unmatched by any other production
method, included hollow parts, especially for medical equipment, with very
thin walls and internal geometrical
complexity.
RFID chips integrated into larger
components by AM, were readable
though completely covered by unbroken metal. Significantly greater surface
area had been attained in an Inconel
heat exchanger without an assembly
operation. IN718 turbine discs with
integral blading had replaced investment casting. And pieces could now be
made with combinations of material
properties, for example a porous core
with dense shell or vice versa.
Figure 7: Powder metallurgists in the EAMG Seminar audience displayed great interest in the contributions.
(Copyright © Kenneth JA Brookes 2013)
28
MPR November/December 2013
metal-powder.net
Phase 3: New AM Design
Manufacturing of functional structures
to reduces weight and cost (bionic design)
Phase 2: Substitution
Cost effective manufacturing of raw parts
Substitution of castings
Phase 1: Tooling, Rig and Development
Manufacturing of tooling,
Rig-and development hardware
Figure 8: Presenter Georg Schlick of German
aero-engine manufacturer MTU. (Copyright
© Kenneth JA Brookes 2013)
Figure 9: EOSINT M270 and M280 AM laser
sintering machines at MTO Aero Engines,
Germany.
As part of its extensive research,
Fraunhofer was now going over from
mixed to pre-alloyed powders. Particle
shape and grain-size distribution
were important to the attainment of
even layers during AM and attracting
increased effort, as was the projected
changeover from batch to continuous
production.
Answering questions, Aumond-Kopp
explained that, with metal-powder AM,
selection of either laser or electronbeam melting needed careful consideration of the design. Laser provided
the best surface quality, but EB gave
faster build-up and better mechanical
properties.
Finally, Aumund-Kopp mentioned the
Direct Digital Manufacturing Conference
to be sponsored by Fraunhofer in Berlin
during March 2014.
Additive Manufacturing for Jet Engine
Parts – Today’s Applications and Future
Potentials, Georg Schlick of MTU Aero
metal-powder.net
Figure 10: MTU roadmap to implement additive manufacturing.
Engines, Germany.
As a potential user of high-value
components made by additive manufacturing, it would be hard to better
MTU, not only an important builder
of gas turbines but also the world’s
largest independent provider of MRO
(maintenance, repair and overhaul) for
such important international engine
programmes as the V2500, CFM56,
PW1000G and CF34. Annual revenues
were more than €3.7 billion, of which
14.8% was military and the remainder
commercial.
MTU, said Georg Schlick (Figure 8),
was well past the purely experimental
phase of additive manufacturing and
into development and commercial
production in a number of high-tech
areas. Parts procurement included the
manufacture of rapid prototyping parts,
AM tooling and rig or developmental
hardware. Production plant included
two DMLS (direct metal laser sintering) ‘technology’ machines (M270 and
M280) and four more M280 machines
for production, mainly with IN718
­currently (Figure 9).
Materials capabilities included a
range of alloy steels, as well as established superalloys like IN718 and
MAR-M509, based on nickel and
cobalt respectively, and even newer
high-temperature engine alloys.
The MTU ‘roadmap’ has taken
the company through three phases
(Figure 10), progressing from initial
development through substitution of
existing parts to direct design of components for the new process, taking full
advantage of its potential for weightsaving and cost reduction.
• Phase 1: Tooling, rig and
­development
• Phase 2: Substitution
• Phase 3: New AM design
Schlick took us through the idiosyncrasies of AM design, with many
examples, demonstrating not only the
possibilities of AM generally, but also
their implementation through targeted
powder metallurgy. Figure 11 depicts
some of the parts designed during Phase
3 of the roadmap, of which perhaps the
most notable are sample turbine blades
with extremely complex internal cooling
passages. Serious production of flight
parts was expected in the near future.
This presentation was followed by
arguably the best Q&A session of the
seminar, with frank answers providing
useful practical information. Here’s a brief
summary related to MTU’s AM parts.
• Shrinkage on cooling is modest, but
residual stress is a problem.
• Porosity is very low but MTU is
“trying to do better”.
• With laser melting, thickness
of ­individual layers is typically
20-50µm, depending on particle size
(layers are one particle thick). EBM
(electron-beam melted) layers are
generally thicker, around 100µm.
In spite of this, laser is preferred
because EBM gives a poorer surface
finish and problems in the reuse of
residual powder.
• Fatigue properties are not an issue
at the moment, but could be in the
future.
November/December 2013 MPR
29
was sufficient to provide green strength.
Build rate was about one hour per cm.
Figure 11: Phase 3: new AM design samples.
Figure 12: Phil Reeves, specialist consultant of Econolyst, UK. (Copyright © Kenneth JA
Brookes 2013)
• Post-treatment is sometimes needed,
for example heat treatment of
Inconel, but so far no HIPing.
• Titanium AM components are produced elsewhere, but not yet at MTU.
• To a final question about O2 in
superalloy powder, the answer was
“No problem at the moment. We live
with it.”
Digital Metal, Co-chairman Rolf
Carlström of Höganäs Sweden.
Much of the company’s AM
expertise was derived from its 2011
acquisition of Foubic, with technology quite different from today’s norms
but cemented by its registration of the
trademark ‘Digital Metal’.
Carlström said that, for Höganäs,
additive manufacturing was becoming
30
MPR November/December 2013
more commercial, initially with small
numbers but increasing complexity.
Ink-jet print technology was employed
by the company, with everything at
room temperature. After ‘printing’,
excess powder was blown away from
the ‘build box’, then the parts were
debound and sintered to attain final
strength. Typical layer thickness was 45
m . In mass production, small components could be spaced less than 1mm
apart on a base plate.
Virtually any metallic powder that can
be sintered could be employed. Following
shrinkage of up to 20%, maximum
density was about 95-97%, similar to
that attained by MIM. The ‘ink’ in the
printer is also the binder for the compact,
but no details were given of its composition or other properties, except that it
Additive Manufacturing with Metallic
Powders – Applications, Opportunities
and Expectations, Phil Reeves of
Econolyst, UK.
A specialist AM consultant, Phil
Reeves (Figure 12) provided an overview of metal powders within the fastgrowing industry. He discussed how
layer manufacturing techniques had
evolved from simple prototyping tools
to a set of technologies now used in the
manufacture of production parts.
There was a big leap from prototyping to series production, jewellery being
one industry already taking full advantage of AM capabilities. Current AM
processes included laser and electron
beam melting technologies and metallic
3D printing for binder-based systems.
Layer manufacturing was the most
common today, but EBM gave greater
productivity than laser melting and
3-dimensional ‘jetting’ from ceramic
heads at even higher temperatures was
under development.
Six drivers for the industry were
cited:
• economic low-volume production
• geometric freedom
• increased part functionality
• product personalisation
• environmental sustainability
• new supply chains and retail models.
Medical devices were currently the
largest market for AM. Examples of
items suitable for AM included some
surgical instruments made in millions
and others required only in tiny numbers. The latter group ranged from customised hearing aids in plastic to dental
implants in solid gold. Another production example was the arm holding the
large video screen in each first-class seat
in the latest Boeing airliners.
Reeves claimed to have looked at
more than 280 possible AM products
in the last nine years, although 906
others were NOT suitable. In 2013, at
least US$350 million would be spent
on R&D, and the total AM market
would rise spectacularly from US$2.2
billion in 2012 to an expected US$6.5
billion in 2020. Most of the production
costs went on processing, so products
were relatively price insensitive where
­materials were concerned.
metal-powder.net