Aluminum Foam

What is aluminum foam?

Duocel® aluminum foam is a true metal skeletal structure with a rigid, highly porous and permeable structure and has a controlled density of metal per unit volume.

The matrix of cells and ligaments is completely repeatable, regular, and uniform throughout the entirety of the material.

It is not a sintered, coated, or plated product. Its purity is typically that of the parent alloy metal, with no voids, inclusions, or entrapments.

Aluminum is our most popular metal foam.  It works very well for heat transfer applications.

Thermal Conductivity

Aluminum has great thermal conductivity for its cost and weight. Because of the high surface area of Duocel® foam, heat transfer to/from fluids flowing through the foam is greatly accelerated over solid aluminum and aluminum fins.

Duocel® aluminum foam is also ideal for use with phase change materials (PCM) because of the large amount of surface area, which increases coupling to PCM.

Please visit our thermal conductivity page in the technical data section for a more in depth explanation of how materials and properties effects the thermal conductivity of Duocel® foam.

Crush Strength

When a load is applied to a foam structure, it will initially yield elastically. However, at approximately 4-6% of strain, depending on the sample size, the foam structure will begin to buckle and collapse continuously at a relatively constant stress. Depending upon the initial relative density of the foam, this constant collapse will proceed to approximately 50-70% of strain. At that point, the stress / strain curve will begin to rise as the compressed foam enters the “densification” phase.

The point in the stress / strain curve where it transitions from the elastic to plastic deformation phase defines the “crush strength” of the foam. This is an important mechanical parameter as it is obviously essential to remain below that level for any structure that is being designed to maintain its shape under design load

Please visit our energy absorption page in the technical data section for a more in depth explanation of how materials and properties effects the crush strength of Duocel® foam.

Electrical Conductivity

Most grades of aluminum are very good conductors of electricity. This allows Duocel® aluminum foam to act as a a grounding medium and as an electrode in electrical applications

Duocel® aluminum foam has also been used to block electromagnetic radiation. This is due to the enormous amount of surface area of the foam.

Please visit our electrical conductivity page in the technical data section for a more in depth explanation of how materials and properties effects the electrical conductivity of Duocel® foam.

Density

We manufacture our foam from solid metal, which already has a low density. The resulting foam is extremely lightweight and is commonly used in weight sensitive aerospace applications. We have the capacity to reduce the foam to a relative density of 3% to 12%. Higher densities can be achieved through post foaming compression.

Duocel® also has a high strength-to-weight ratio. It is a great material for lightweight structural applications.

Density can be customized to obtain ideal pressure drop while high surface area to volume ratio and increased tortuosity make aluminum foam the ideal medium for products such as aircraft air oil separators.

Sizes

For our Duocel® foam we are limited to continuous sizes that fit into either 5″ x 7″ x 18″ or 4″ x 14″ x 16″. For pieces any larger we are able to use multiple pieces and bond or braze them together. Please contact us to discuss availability and custom sizing.

Coatings

Duocel® foam can be anodized, chem filmed, and metal plated just as solid aluminum for increased corrosion resistance and/or higher thermal conductivity.

Corrosion Resistance

Aluminum naturally has a tough oxide layer that helps prevent corrosion. This layer is normally stable from 4.5 to 8.5 pH. Within that pH range, aluminum is very corrosion resistant.

Aluminum foams are susceptible to galvanic reaction.

Magnetism

Though none of our normally foamed materials are magnetic, they can be nickel plated for magnetism.

Characteristics

  • Low Density
  • High Strength to Weight Ratio
  • High Surface area to Volume Ratio
  • isotropic load response
  • controlled stress-strain Characteristics
  • Can be Heat Treated
  • Brazable
  • Can be coated and plated

General Properties

Density Range3-12%
Max Compression70%+
PPI Available5, 10, 20, 40
Alloys6101*, 6061, 7075, 1100

*Standard Alloy

Aluminum-Foam