Magnesium Oxide – MgO

Our electrically Fused Magnesium Oxide extruded cores and dry pressed bushings and spacers have good electrical insulating properties with the added benefit, offering good thermal conducting properties at elevated temperatures.  Typical applications include, but not limited to, cartridge heaters, thermocouples, mineral insulated cable, high watt density heaters as well as other temperature sensing devices.

Material Specifications
Material Magnesia
S-464 S-461
Chemical Analysis
MgO, % 96.0 min 99.4 min
AL2O3, % .40 max .15 max
SiO2, % 2.6 max .15 max
CaO, % 1.5 max .35 max
Fe2O3, % .2 max .15 max
B+Cd, ppm 400 max 30 max
Mechanical Properties
Porosity, % MIN 12 MIN 14
Bulk Density, gm/cc 2.33 2.38
Flexural Strength, psi 2,000-10,000 2,000-10,000
Compressive Strength, psi 5,000-15,000 2,000-15,000
Thermal Properties
Thermal Expansion 25°-700° inch/inch/°Cx10-6 12.4 12.7
Note: This information is for design guidance only. Du-Co will not guarantee this information as absolute values. Various geometries can affect properties