Alumina-Silica Refractory Insulation
Ceramic Fibre
Ceramic fibre insulation handles temperatures far beyond conventional gasket materials. We use it for furnace doors, kiln linings, and exhaust system seals where nothing else survives. We supply ceramic fibre in blanket, board, paper, and rope forms for high-temperature insulation and sealing in steel, glass, ceramics, and power generation industries.
At a Glance
Temperature Range
Standard RCF blanket 1000 °C continuous (1050 °C peak with derating); high-purity RCF to 1300 °C continuous; AES grades to ~1100 °C continuous
Thickness Range
1 mm (paper) to 50 mm (blanket)
Available Forms
Colours
Technical Properties
Typical values across stocked grades. Specific grade data sheets available on request.
Physical Characteristics
Density
64–400 kg/m³ (form dependent)
Tensile Strength
50–100 kPa, blanket (low; insulation only)
Chemical Resistance
Resistant To
- Most non-ferrous molten metals at moderate superheat (non-wetting to aluminium, copper, zinc; verify contact time and temperature for specific metal)
- Oxidising atmospheres at high temperature
- Neutral and mildly acidic process gases
- Mineral oils (at temperatures below decomposition)
Limited Resistance
- Phosphoric acid (attacks at elevated temperature)
- Strong alkalis at high temperature (dissolve silica phase)
- Reducing atmospheres (may alter fibre structure over time)
Not Recommended
- Hydrofluoric acid — rapidly attacks the silicate fibre structure
- Concentrated alkalis at high temperature, which dissolve the silica binder
- High-velocity gas streams, where erosion removes fibres. Use board or rigidised forms.
Environmental Ratings
Flame Rating
Non-combustible (classified as non-combustible per AS 1530.1)
Standards & Certifications
Standards Compliance
Common Applications
- Furnace and kiln door gaskets and seals
- Ladle and tundish linings (steelmaking)
- Expansion joint packing in high-temperature ductwork
- Exhaust manifold and turbo heat shields
- Boiler and incinerator insulation
- Glass annealing lehr seals
- Chimney and flue linings
- Fire protection barriers and wraps
Not Recommended For
- Low mechanical strength. Ceramic fibre is insulation, not a structural or pressure-sealing material
- Standard and high-purity RCF are classified Carc. 1B (H350i) under EU CLP and IARC Group 2B. Engineering controls, P3 respiratory protection, and dust suppression are required during cutting, installation, and removal — refer to Safe Work Australia code of practice. Specify AES grades where the application allows to avoid the carcinogen classification
- RCF is on the REACH SVHC candidate list (since 2010-01-13). Communicate this to downstream users on request
- Devitrified RCF (post-service) is more friable and releases respirable fibres more readily — apply enhanced controls when removing aged insulation
- Shrinks at sustained temperatures near classification limit, so derate continuous use temperature by ~10%
- Not suitable for high-velocity gas erosion (fibres break loose). Use rigidised or board forms for gas-facing surfaces.
- Devitrification (crystallisation) occurs above continuous use temperature, making fibre brittle and reducing insulation value
- Not approved for transformer insulation per IEC 60076-1 — specify mica, calcium silicate, or aramid paper for transformer applications
Available Grades
Ceramic Fibre Blanket (RCF, 1260 °C classification)
Flexible alumina-silica blanket for furnace linings, expansion joints, and thermal wrapping. Standard 128 kg/m³ blanket rated 1000 °C continuous, 1050 °C peak. Classified Carc. 1B under EU CLP — specify AES grade where the application allows.
Ceramic Fibre Board (1260 °C)
Rigid vacuum-formed board for structural insulation and high-temperature backing. Self-supporting and machinable for precise gasket and seal shapes.
Ceramic Fibre Paper (1260 °C)
Thin, flexible paper form for gaskets, inter-layer insulation, and wrapping. Typically 1–6 mm thick, used where blanket is too bulky.
Ceramic Fibre Rope
Round or square braided rope for furnace door seals, expansion joint packing, and flue gas sealing. Available in multiple diameters.
High-Purity Ceramic Fibre (RCF, 1425 °C classification)
Higher-alumina RCF (~72–75% Al₂O₃) for service to 1300 °C continuous in speciality furnaces, glass manufacturing, and extreme-temperature applications. Still classified Carc. 1B under EU CLP — specify only where AES temperature limits are inadequate.
AES Low-Biopersistent Mineral Wool
Alkaline earth silicate (AES) fibre — calcium-magnesium-silicate composition with biopersistence half-life <10 days in lung tissue, meeting Note Q exemption to EU Regulation 1272/2008. As a result, AES is NOT classified as a carcinogen under EU CLP, IARC, or REACH SVHC — the substitution rationale for replacing standard RCF where temperature allows. Classification temperature ~1200 °C with continuous use to ~1100 °C. Suited to furnace-door, expansion-joint, and duct-sealing applications below the high-purity RCF threshold.
Related Materials
Need Ceramic Fibre?
We supply ceramic fibre in sheet, roll, and custom die-cut forms. Contact our team for pricing, data sheets, or technical assistance.
Disclaimer
This resource is provided for general engineering reference only and does not constitute professional advice, specification, or guarantee of performance. Actual results depend on specific application conditions. Universal Gaskets Pty Ltd accepts no responsibility or liability for decisions made based on this information. For full terms, see our Terms & Conditions.