SG-70 (2300ºF Refractory Matrix Composite Board)

SG-70 is a non-asbestos ceramic refractory reinforced with continuous fibers to increase the toughness, structural reliability and overall performance of the ceramicell nameomposite. Supplied in sheets, boards, cylinders and other geometric shapes, SG-70 exhibits non-brittle behavior and can withstand extreme thermal shock and cycling within its specified temperature range. Chemically inert, unaffected by moisture and non-wetting to non-ferrous metals, SG-70 is machinable with standard tools. Thermally and electrically insulating, SG-70 is an excellent material choice for a variety of structural applications. Compared to SG-50, the SG-70 material has a more homogeneous fiber reinforcement structure which allows for intricate machining (i.e. counter-boring). It also has a higher service and ultimate use temperature than the SG-50 material.

Other sheet/cylinder sizes and thickness and geometric shapes are available upon request – please inquire.


Density ( lb/ft³ )130
Density ( g/cc )2
Flexural Strength ( MPa )58
Flexural Strength ( psi )8400
Sheet Size ( in )
Porosity ( % )30
Maximum Use Temperature ( ºC )1260
Maximum Use Temperature ( ºF )2300
Dielectric Strength ( V/mil )91
Compressive Strength ( MPa )85
Compressive Strength ( psi )12325
Thickness ( in )1/8 to 1/2
Sheet Thickness ( in )1/32
Typical CompositionAl2O3 - 70%
Other Metal Oxides - 10%
SiO2 - 20%
Length ( in )up to 84
Dielectric Constant5.5
Sheet Area ( ft )4 x 4
Thermal Conductivity at 1000ºC (1832ºF) ( BTU-in/hr-ft²-ºF )4.9
Thermal Conductivity at 1000ºC (1832ºF) ( W/m-ºK )0.7
Structural Use Temperature ( ºC )816
Structural Use Temperature ( ºF )1500
Thermal Conductivity at 205ºC (400ºF) ( BTU-in/hr-ft²-ºF )4.2
Thermal Conductivity at 205ºC (400ºF) ( W/m-ºK )0.6
Thermal Conductivity at 425ºC (800ºF) ( BTU-in/hr-ft²-ºF )4.41
Thermal Conductivity at 425ºC (800ºF) ( W/m-ºK )0.63
Thermal Conductivity at 625ºC (1200ºF) ( BTU-in/hr-ft²-ºF )4.69
Thermal Conductivity at 625ºC (1200ºF) ( W/m-ºK )0.67
Linear Shrinkage, 24 hrs. Isothermal Soak at 870ºC (1500ºF) ( % )1/2
Linear Shrinkage, 24 hrs. Isothermal Soak at 1260ºC (2300ºF) ( % )1
Electrical Resistivity ( ohm-cm )52 x 1010
Inner Diameter ( in )2 to 36
Engineered Shapes (Cylinders & Shapes)
Machined Parts (Cylinders & Shapes)


MarketsSpecific Applications
Specialty Furnace ComponentsBottom Supports for Quartz Furnaces
Hard Face Furnace Lining
Low Temperature Kiln Furniture
Specialty High Temperature & Electrical InsulationCorona Plastic Treating in Printing Process
Internal Lining for Glass Tempering Furnaces
Electrical Resistor Grids in Locomotive Dynamic Systems
Specialty Metal Working ComponentsInsulator Between Press Platens in Plastic Forming of Titanium
Compression Plate InsulationElectric Insulator for Induction Pressing Diamond Saw Segment
Platen or Mold Insulation for High Temperature Presses
Non-Ferrous Metal Handling EquipmentAluminum Filter, Homogenizer and Purifier
Crustbreaker Plunger hace Aluminum Holding Furnace
Skimmer Dams & Baffles
Specialty Structural Insulation Components
Induction Furnace ComponentsChannel Melter Components (Brass Foundry)
Coil Liners, Channel Melters, Box Plates
Coreless Induction Furnace Components
Cover, Top, Rase, Side, Front and Bark Plates, Coil Posts
Coil Support, Upper Fitting, Spacer, Riser Blocks, Splash and Coil
Shields, Crucible Hold Downs, Coil Support Spacer Rings
Utility/EnergyTubesheets, Candle Filters

This information, which is subject to change, is offered solely for your consideration and is not a warranty or representation for which we assume legal responsibility.


  • Asbestos-Free
  • Use Temperatures to 1260ºC (2300ºF)
  • Chemical Inertness
  • Non-Wetting to Non-Ferrous Metal
  • Unaffected by Moisture or Water
  • Non-Brittle
  • Abrasion Resistance
  • Thermal Shock Resistance
  • Good Reflectivity
  • Low to Negligible Shrinkage
  • Excellent Dimensional Stability
  • Machinable with Standard Tools
  • High Dielectric Strength / Electrical Resistivity
  • Little or No Outgassing
  • Good Bending Strength
  • Good Compressive Strength

Competitive Products

  • RS100/101, 200/201
  • Metal / Steel
  • Plastics
  • Dense Asbestos
  • Machinable Ceramic
  • Cordierite
  • Vacuum-formed Shapes
  • Castable Ceramics

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