Ceramic foam
Description
A stiff, lightweight foam made from ceramics. Ceramic foams are usually manufactured by impregnating open-cell polymer foams internally with ceramic slurry and then firing in a kiln, leaving behind only ceramic material. This produces an open-cell structure that has 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. Surprisingly, foamed ceramics exhibit a toughness and strength that bulk ceramics do not have. This is because, when a crack occurs, its travel stops at an open-cell, rather than propagating through the material.
Synonyms and Related Terms
Foamed ceramic;
Commercial products: Duocel (ERG); Techfil (Tech Ceramic)
Applications
- thermal insulation, acoustic insulation
- adsorption of environmental pollutants
- filtration of molten metal alloys
Physical and Chemical Properties
- Resistant to acids and oxidation
- Relative density = 4-30% (compared to bulk material)
- Compressive strength = 2800 psi (Duocel Silicon carbide foam at 10-12% relative density)
- Mohs hardness = 9 (Duocel Silicon carbide foam at 10-12% relative density)
Resources and Citations
- American Elements: Foams
- Wikipedia: Ceramic foam
- Tech Ceramic: Ceramic foams
- ERG: Duocel Ceramic foam