Alumina fiber-based heat-insulation board

TOMBO™ No. 5461


RF BOARD is a product made by adding inorganic and organic binders to alumina fiber and then molding this into a board form.
As it is made of a fiber-based board, it has little heat storage volume. It can be used to design compact furnaces thanks to its excellent thermal insulation properties and workability.
Nichias has a lineup of various dense boards that are suitable for working temperatures of 1, 400°C to 1, 800°C or parts used in such an environment.
Therefore, it performs really well as a lining material for ultra-high-temperature electric furnaces and various high-temperature furnaces.

Product Category

Thermal Insulation MaterialUp to 1500℃


Energy (Electricity, Gas, Heat Supplies)Thermal Power Stations (Coal)Thermal Power Stations (LNG)Nuclear Power StationsHydrogen and AmmoniaBiomass Power Generation and Heat Supply PlantsElectronicsSemiconductors & Flat Panel Displays (FPD)Electronic Components5GBatteries & Electricity Storage SystemsCarbon Neutrality and DecarbonizationIndustrial-Use InsulationEnergy Saving ProposalsHydrogen and AmmoniaBiomass Power Generation and Heat Supply PlantsVarious Plant FacilitiesIndustrial Furnaces (Electric Furnaces/Combustion Furnaces)


It offers excellent workability.
It is lightweight and has low thermal conductivity, and so it displays excellent insulation performance.
It is chemically stable.
It can be manufactured into a processed product or molded product.


Lining material for electrical furnaces that rapidly rise and drop in temperature
Lining material for various high-temperature furnaces
Lining material for electrical component ovens

Quality characteristics

Item TOMBO No.
5461-16LDA 5461-17MDA 5461-18HD 5461-18HDS
Product name RF BOARD
Color White
Density (kg/m3) 200 400 500
Maximum heat resistant temperature (°C) 1600 1700 1800
Bending strength (MPa) under normal state 0.7 1.5 1.4 1.3
Heat shrinkage rate (%)
[After 24 hours of heating]
Ignition Loss(%)
3 3 3 0
*The values above are our actual measurement values. They are not standard values.

Standard dimensions and quantity

Item TOMBO No.
5461-16LDA 5461-17MDA 5461-18HD 5461-18HDS
Standard dimensions Width × length (mm) 600×900
Quantity Thickness 25 mm 4
Thickness 40 mm 2
Thickness 50 mm 2
*Feel free to contact us about other sizes.


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