Medium Alumina Bricks

High Alumina Bricks are alumina-silicate refractory with more than 48% Al2O3 content. High Alumina Bricks are manufactured with alumina or other raw materials containing higher alumina content through molding and firing. High Alumina Brick can resist acid slag erosion resistance because of its neutral refractory property. High Alumina Bricks have high thermal stability and refractoriness over 1770℃.

According to different Al2O3 content, High Alumina Bricks can be classified into Three Grades in China.

  • Grade I High Alumina Bricks have more than 75% Al2O3 content.
  • Grade II High Alumina Bricks have 60~75% Al2O3 content.
  • Grade III High Alumina Bricks have 48~60% Al2O3 content.

Performance Characters:

  • Good resistance to corrosion and abrasion
  • Perfect thermal shock resistance
  • Good spalling resistance
  • High mechanical strength
  • Good volume stability under high temperature
Main Application:

Mainly used for carbon furnace, baking furnace, heating boiler, glass furnace, cement kiln, gasification furnace, blast furnace, hot blast stove, coking furnace, furnace, casting and casting steel brick, etc.

Alumina Bricks

High Alumina BricksAl-48Al-55Al-70Al-75Al-80Al-85
Al2O3 (%)≥48≥55≥70≥75≥80≥85
Fe2O3 (%)≤2.5≤2.5≤2.0≤2.0≤2.0≤1.8
Refractoriness (°C)176017601770177017901790
Apparent porosity (%)≤23≤23≤23≤23≤22≤22
Bulk density (g/cm3)2.302.352.402.462.682.72
Refractoriness under load 0.2MPa (°C)142014701510152015301550
Cold crushing strength (MPa)454560606570
Permanent linear change (%)1500 °C × 2h-0.4 to 0.1-0.4 to 0.1-0.4 to 0.1-0.4 to 0.1-0.4 to 0.1

High Alumina BricksHA60HA70HA75HA80
Al2O3 (%)≥ 60≥ 70≥ 7578-80
SIO2 (%)322220≥ 18
Fe2O3 (%)≤ 1.7≤ 2.0≤ 1.8≤ 1.8
Na2O+K2O (%)< 2.3< 2.0< 1.2/
Refractoriness>1790>1800>1825≥ 1850
Refractoriness under load 0.2MPa (°C)1450>1510>1530≥ 1550
Porosity (%)22<22<2120
Bulk density (g/cm³)2.332.43-2.482.40-2.502.55
Cold crushing strength (MPa)≥ 45≥ 50≥ 54≥ 60

Technical data for other firebricks are available upon request.