METAL AND CERAMIC FOAMS INFORMATION CENTER
A metallic foam or ceramic foam is a cellular structure consisting of a solid metal or ceramic material containing a large volume fraction of gas-filled pores. The pores can be sealed (closed-cell foam) or can form an interconnected network (open-cell foam). The defining characteristic of these foams is a very high porosity, with typically 75-95% of the volume consisting of void spaces. The strength of foamed material possesses a power law relationship to its density: for example, a 20% dense material is more than twice as strong as a 10% dense material. Metallic foams typically retain some physical properties of their base material. Foam made from non-flammable metal will remain non-flammable and the foam is generally recyclable back to its base material. The coefficient of thermal expansion also typically remains similar, while thermal conductivity is likely to be reduced.
Types of Foams
Open-Cell Metal Foams. Open celled metal foams are usually replicas using open-celled polyurethane foams as a skeleton. These foams have found a wide variety of applications in heat exchangers, energy absorption, flow diffusion and lightweight optics. Extremely fine-scale open-cell foams are used as high-temperature filters in the chemical industry. Metallic foams used in compact heat exchangers increase the heat transfer at the cost of an additional pressure drop. However, their use permits the physical size of a heat exchanger to be reduced substantially, and therefore also the fabrication costs.
Closed-Cell Metal Foams. Closed-cell metal foams have been developed since the 1950s, but although prototypes were available, commercial production was started only in the 1990s. Close-celled metal foams are commonly made by injecting a gas or mixing a foaming agent into molten metal. The material is then stabilized using a high temperature foaming agent (usually nano- or micrometer sized solid particles). The size of the pores, or cells, is usually 1 to 8 mm. Closed-cell metal foams are primarily used as an impact-absorbing material. Unlike many polymer foams, metal foams remain deformed after impact and can therefore only be used once. They are light, typically 10-25% of the density of the metal they are made of, which is usually aluminum, and stiff. Closed-cell foams retain the fire resistant and recycling capability of other metallic foams but add an ability to float in water.
Ceramic Foams. Ceramic foam is usually manufactured by impregnating open-cell polymer foams internally with ceramic slurry and then firing in a kiln, leaving only ceramic material. The foams may consist of several ceramic materials such as aluminum oxide. The foam is often used for thermal insulation, acoustic insulation, adsorption of environmental pollutants, filtration of molten metal alloys, and as substrate for catalysts requiring large internal surface area. It has also been used as stiff lightweight structural material, specifically for support of reflecting telescope mirrors.
American Elements maintains industrial scale production for all its foam products. and will execute Non-Disclosure or Confidentiality Agreements to protect customer know-how.
AE Foams™ products include:
Recent Research & Development for Metal and Ceramic Foams
- A metal-decorated nickel foam-inducing regulatable manganese dioxide nanosheet array architecture for high-performance supercapacitor applications. Tang PY, Zhao YQ, Wang YM, Xu CL. Nanoscale. 2013 Jul 25.
- Three-dimensional B,N-doped graphene foam as a metal-free catalyst for oxygen reduction reaction. Xue Y, Yu D, Dai L, Wang R, Li D, Roy A, Lu F, Chen H, Liu Y, Qu J. Phys Chem Chem Phys. 2013 Aug 7;15(29):12220-6.
- Photodecomposition of humic acid and natural organic matter in swamp water using a TiO(2)-coated ceramic foam filter: potential for the formation of disinfection byproducts. Mori M, Sugita T, Mase A, Funatogawa T, Kikuchi M, Aizawa K, Kato S, Saito Y, Ito T, Itabashi H. Chemosphere. 2013 Jan;90(4):1359-65.
- Spectroscopic studies of dye-surfactant interactions with the co-existence of heavy metal ions for foam fractionation. Zhang D, Zeng G, Huang J, Bi W, Xie G. J Environ Sci (China). 2012;24(12):2068-74.
- Enhanced hydrogen storage by spillover on metal-doped carbon foam: an experimental and computational study. Psofogiannakis GM, Steriotis TA, Bourlinos AB, Kouvelos EP, Charalambopoulou GCh, Stubos AK, Froudakis GE. Nanoscale. 2011 Mar;3(3):933-6.
- Synthesis and application of alizarin complexone functionalized polyurethane foam: preconcentration/separation of metal ions from tap water and human urine. Azeem SM, Arafa WA, el-Shahat MF. J Hazard Mater. 2010 Oct 15;182(1-3):286-94.
- Image analysis of soft-tissue in-growth and attachment into highly porous alumina ceramic foam metals. Khalil A, Aponte C, Zhang R, Davisson T, Dickey I, Engelman D, Hawkins M, Mason M. Med Eng Phys. 2009 Sep;31(7):775-83.
- Modelling a ceramic foam using locally adaptable morphology. Lautensack C, Giertzsch M, Godehardt M, Schladitz K. J Microsc. 2008 Jun;230(Pt 3):396-404.
- Preparation, characterization and applications of novel iminodiacetic polyurethane foam (IDA-PUF) for determination and removal of some alkali metal ions from water. El-Shahat MF, Moawed EA, Burham N. J Hazard Mater. 2008 Dec 30;160(2-3):629-33.
- Fibroblastic interactions with high-porosity Ti-6Al-4V metal foam. Cheung S, Gauthier M, Lefebvre LP, Dunbar M, Filiaggi M. J Biomed Mater Res B Appl Biomater. 2007 Aug;82(2):440-9.