Ceramic foam

Jump to navigation Jump to search
SEM image of Silicon carbide foam (15x) from ERG Aerospace


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)


  • 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