Advanced Pore Morphology (APM) Foams
Fraunhofer Institute
for Manufacturing and
Advanced Materials
IFAM
Shaping
and
Functional Materials
Prof. Dr.-Ing. Matthias Busse
Wiener Straße 12
D-28359 Bremen
www.ifam.fraunhofer.de
Concept
At the Fraunhofer Institute for
Manufacturing and Advanced Materials (IFAM) an advanced process
route of the well established powder-metallurgical process for the
production of foamed metals
(FOAMINAL®) has been developed
and patented. In contrast to the
FOAMINAL® process (near net
shape foam parts) the general concept of the APM technology is the
separation of two main process
steps:
1. Foam expansion
2. Foam part shaping
APM foam parts consist of small
volume metallic foam elements
which are expanded in bulk/mass
production. Joined to each other in
a separate process step the foam
elements form the APM foam part.
Characteristics
• pore morphology / mechanical
properties adjustable independent of part’s geometry and volume
• Max. volume of largest pore for
complete part volume guaranteed
• Homogeneous,
multi-phase
and/or local gradient pore structures possible
• Mono-, bi- or multi-modal combinations/mixtures of APM foam
elements with different properties (densities, geometry, matrix
material) possible
• Integral APM foam part density
(0.3 to 1.0 g/ccm for Al alloys)
defined adjustable
• Surface structure of APM foam
parts is determined by the geometry of the single elements
and the employed joining process.
Dr. Gerald Rausch
phone
+49-421-2246-242
fax
+49-421-2246-300
[email protected]
Karsten Stöbener
phone
+49-421-2246-117
fax
+49-421-2246-300
[email protected]
Joachim Baumeister
phone
+49-421-2246-181
fax
+49-421-2246-300
[email protected]
Fig. 1: APM elements (middle: adhesive coated) and filled structure
APM foam properties and application areas
Fraunhofer IFAM continuously further develops the APM technology.
Statistically verified properties will
be published in near future. Currently available results show, that
APM foam parts have similar /
partly improved properties compared to FOAMINAL® parts (with
similar density). Application areas
for APM foam parts are:
• Energy absorbing structures
• Stiffening elements for thinwalled shell structures
• Sandwich structures with APM
foam element core layer
• Vibration attenuation
• Packaging
• Melt covers (metal melts)
APM foam elements (standard)
APM foam parts
With the APM technology pure
APM foam parts as well as APM
foam containing compounds can
be produced in three processs
steps:
1. Supply of e.g. adhesive coated
APM foam elements by IFAM
(see fig. 1, middle)
2. Puoring of the APM foam elements into a mould or a hollow
structure to be foam filled.
3. Activation/Curing of adhesive
coating by heat treatment, e.g.
180 °C for 30 min..- finished !
(see fig.1, right)
Currently IFAM can offer an adhesive coating with a reactive hotmelt. The coating is non-tacky at
RT and thermally stable up to 100
°C after curing.
• Diameter: 5, 10, 15 mmr
Besides adhesive bonding other
joining processes (e.g. pressing,
sintering) for joining the single
APM elements are in development.
• Shape: spherical
APM sandwich structures
• Material: AlSi 7
• Density: 0.5 to 1.0 g/cm3
Fig. 2: APM foam elements
APM foam elements can also be
employed as core layer for
lightweight sandwich structures
(fig. 3). The e.g. adhesive coated
APM elements are placed between
the surface sheets. In a hot press
the adhesive is activated and cured
for joining all layers to form the
sandwich structure. Adhesive and
surface
layers
(material
and
thickness) can be adjusted according
to the desired application.
Abb. 3: APM-Sandwich
Serial production and costs
APM foam parts and sandwich
structures are produced from standard APM foam elements, which
can be produced in and handled
with standard equipment for bulk
material. Therefore the whole
process chain can be fully automated. Avoiding thermally stable
foaming moulds improves the
process efficiency. In total a competitive material price has been
estimated for large scale serial APM
foam part production.
What IFAM can do for you:
• Feasibility studies and APM
foam part development
• Supply of standard APM foam
elements (as produced or adhesive coated)
• Production
of
specifically
customised APM elements and
foam parts
• Training courses, workshops
and technology demonstrations
• Licensing
and
technology
transfer of the patented APM
metal foam technology