Al2O3–SiO2 (RCF) / alkaline earth silicate (AES)
ChemistryCeramic fibre is specified as Al2O3–SiO2 (RCF) / alkaline earth silicate (AES). Density band 64–192 kg/m³ blankets.
Darker cells mean a higher score for this topic on that metric.
Strength14
Heat resistance98
Fire performance97
Insulation80
Workability50
Circularity34
LessMore
Last reviewed Sources & creditsMedia creditsMethodology
Quick answers
Is Ceramic fibre non-combustible?
Declared reaction class in this atlas: A1. Assemblies still need resistance tests.
Does Ceramic fibre insulate?
Thermal mark 80/100 versus the atlas. Conductivity note: λ rises with T; still far below brick.
What is the density band?
64–192 kg/m³ blankets
How is it made?
Origin story: 1940s–60s US/JP; EU RCF classification 1990s (United States / Japan / EU).
Can it be recycled?
Circularity mark 34/100 — editorial, route-specific.
Typical melting or failure heat?
classification T often 1260–1400 °C
heat 98 · fire 97
What holds Ceramic fibre together is not the nickname. Formula Al2O3–SiO2 (RCF) / alkaline earth silicate (AES), density 64–192 kg/m³ blankets.
Meters are atlas-relative. Grades are the SKUs buyers write.
Phases
Microstructure
OrderProcessing sets grain, crystallinity or fibre orientation — the reason two lots of Ceramic fibre can test differently.
Interfaces
SurfacesCoatings, oxide films, sizings or paper faces often decide weather and fire behaviour more than the bulk brochure.
Defects
FlawsInclusions, voids, knots, pinholes or residual stress start the failures that mill certificates do not list.
Grades
VariantsCeramic fibre is a family. Grade names below are the ones buyers actually write on RFQs.
Ageing
TimeMoisture, UV, creep, hydrogen or carbonation shift properties in service. Design to the aged state.
Relative meters
Strength14
Strength is an editorial 0–100 mark relative to the other 31 materials in this atlas — not a laboratory certificate.
Heat envelope98
Heat envelope is an editorial 0–100 mark relative to the other 31 materials in this atlas — not a laboratory certificate.
Fire behaviour97
Fire behaviour is an editorial 0–100 mark relative to the other 31 materials in this atlas — not a laboratory certificate.
Insulation80
Insulation is an editorial 0–100 mark relative to the other 31 materials in this atlas — not a laboratory certificate.
Workability50
Workability is an editorial 0–100 mark relative to the other 31 materials in this atlas — not a laboratory certificate.
Circularity34
Circularity is an editorial 0–100 mark relative to the other 31 materials in this atlas — not a laboratory certificate.
Grades
RCF 1260
Classic alumino-silicate.Classic alumino-silicate.
AES 1200
Lower biopersistence claims.Lower biopersistence claims.
PcW polycrystalline
Higher T.Higher T.
Modules
Heater walls.Heater walls.
Papers / felts
Gaskets.Gaskets.
Bonds
Primary bonding
Ceramic fibre holds together by ionic/covalent networks.
Secondary forces
Hydrogen bonds, van der Waals stacks or grain-boundary cohesion set toughness and moisture uptake.
Composites & fills
Fillers, fibres, plasticisers or aggregates are part of the real product, not impurities.
Environment film
Oxides, chars, sizings or paints are the layer the world actually meets.
Change the grade, the coating or the moisture and you have a different material with the same English name.
Keep exploring
More in Fire performance
🏠
Gypsum board
CaSO4·2H2O panels that buy fire time by calcining — the everyday A2/A1 lining of interiors.
Overall 59 👨🚒Nomex
DuPont’s meta-aramid — fire-fighter turnout, electrical paper and a char that does not melt-drip like nylon.
Overall 65 🧯Intumescent coating
Paints that swell into insulating char — the thin-film way to give steel an R-rating without bulky boards.
Overall 58