Characteristics of closed cell aluminum foams

Production Process for Production Process for Aluminum Foam Parts Mold Extrusion press F Press CIP... Aluminum foam insert used for stiffening and energy absorption in auto side rail...

Characteristics of Closed Cell

Aluminum Foams

„ Efficient energy absorption

„ Excellent stiffness-to-weight ratio

„ Nearly isotropic - Multiaxial loading

„ Low thermal conductivity

„ Fire resistant

„ Shock wave attenuation

„ Sound and vibration damping and absorption

„ Tailorable density and properties

„ Recyclable

Production Process for

Production Process for

Aluminum Foam Parts

Mold

Extrusion press

F Press

CIP

Al Foams: Flat plates and 3-D shapes for cores in lightweight aluminum castings

Quasi-Static Behavior of Aluminum Foam

Aluminum Foam Filled 304SS Tubes

After Axial Compression

3-D molded foam shape for auto crash energy absorption

Aluminum foam insert used for stiffening and energy absorption in auto side rail

Tailorability of Aluminum Foams

Plateau stress of Al-12Si foams as a function of foam density

Tailorability of Aluminum Foams

Aluminum Foam Used in Hybrid Vehicle Armor

Alumina Ceramic Aluminum Foam Fiber reinforced polymer

Cross-section through lightweight armor using aluminum

foam layer, after 20 mm FSP ballistic testing for the U.S Army

Aluminum foam impedance layer provides:

• Improved defeat of projectile

• Enhanced ballistic shock wave attenuation

• Lower dynamic deflection of backplate

Aluminum Foam Frame for Ballistic

Stress Wave Management

Force measurements for shots 13-16 Without Al Foam vs With Al Foam

External Aluminum Foam

Frame Offset Impact

0 0.2 0.4 0.6 0.8 1 1.2 -30

-25 -20 -15 -10 -5 0

2

0 2 4 6 8 -8

-6 -4 -2 0 2 4 6 8 10

3 TEX -4A -3 W ith AL f oam

External Aluminum Foam

Frame - Center Impact

Vibration Damping Tests on Al Foam

and Bulk Al Sheets

Weight (kg)

Area (mm)

Test apparatus for vibration damping measurements

Tested panel

Acceleration sensor

Impact hammer

with force

sensor

Frequency Response Curves

After Impact by Hammer

Damping of vibration after impact by hammer

as measured by surface accelerometer

-400 -300 -200 -100 0 100 200 300

Damping factor (decay) of 25 mm Al foam panel vs 3 mm and 5 mm Al sheets

Aluminum Foam Blast Testing

Blast Loading of Aluminum Foam Panels

Test Configuration (18 in x 18 in test area)

No back plate deflection

Steel plates deformed but not perforated

Blast test panels after exposure to detonation

of 1 kg PETN at 0.1 m standoff distance

Left: Front steel sheet – 1/8 in thick Center: Aluminum foam

Right: Back steel plate - 1/4 in thick

Compressive plastic deformation and fracture

of aluminum foam exposed to 1 kg PETN explosive

at 0.1 m standoff

Aluminum experienced up to 70-80%

compressive strain in local regions under

1/8 in thick steel front cover sheet

Aluminum Foam Sandwich Panels

alloy face sheets

stiffness-to-weight and strength-to-weight ratios

to 4 inch thick

Aluminum Foam Sandwich panels in various thicknesses

Unfoamed AFS precursor sheets

3100 x 1100 x 2.5 mm

AFS plate 1000x1000x30 ±0,5

AFS heavy plates

Aluminum Foam Sandwich Panels

„ Current AFS panels size: 1350 x 1700 x 9 to 80 mm thick (53 x 67 x 0.35 to 3.15 in thick)

„ AFS panel size to be available during 4 th Qtr 2007:

Aluminum Foam Sandwich Panels

8 to 100 mm (0.32 to 4 in.)

AFS Panel Face Sheet Alloys

AFS Panel Foam Core Alloys

Specific Bending Stiffness vs Panel Height

Aluminum

Steel

AFS

Faces t=1mm Foam density 0.3

Specific Bending Stiffness of

Aluminum Foam Sandwich Panels

I E m

Nmm kg

Calculated Weight Savings Using Aluminum Foam

Sandwich Panels for Equivalent Stiffness

Weight Savings Using AFS Panels

% Weight Savings

Vibration damping of AFS vs

Steel and aluminum

Joining Methods for AFS Panels

MIG Welding of AFS-Beam

MIG Welding

Welding of AFS

Cube 500x500x500

AFS 0,75/13,5/0,75

Core density 0,28 g/cm3

AFS panels can be formed after foaming to produce closed edges

Life cycle tests of AFS truck crane

100 kN (vertical)

14 kN (sideways) Req N=40,000

Result: No cracks after more than

N=100,000 cycles

Potential Defense Applications

Alulight produces foam panels and 3-D parts

as well as semi-finished components to customer requirements…

… as demanded by specific threats

ƒHigh energy absorption

ƒ Very high specific stiffness