Refractory Mullite Brick

Refractory Mullite Brick

Mullite Brick is a kind of High-aluminum refractories that regard the mullite (Al2O3•SiO2) as the main crystal phase. The average alumina content is between 65% and 75%. In addition to mullite mineral composition, which contains lower alumina also contains a small amount of glass and cristobalite; higher alumina containing a small amount of corundum. High refractoriness up to 1790°C. Load softening starting temperature 1600 ~ 1700 °C. Room temperature compressive strength 70 ~ 260MPa. Good thermal shock resistance.

Performance

  • Good high temperature strength & Good thermal shock resistance.
  • Resistance to most chemical attack & With excellent stability in acid metal slags.
  • Resistance to oxidation and attack  by furnace atmospheres.
  • Resistance to abiasion and Good electrical resistivity.
  • Excellent thermal stability and Maximum service temperature 1700˚C.

Application

The mullite brick adopts the imported plate corundum and high-purity fused corundum as the main raw materials, and adopts advanced ultrafine powder addition technology. After mixing, drying and forming, it is fired in a high-temperature shuttle kiln. So Mullite bricks are widely used in slag gasification furnaces, synthetic ammonia conversion furnaces, carbon black reactors, and refractory kiln furnaces, Furnace roof of hot blast stove, Furnace stack and bottom of blast furnace,Regenerative chamber of glass melting furnace and Ceramic high temperature furnace.

ItemMK60MK65MK70MK75
Al2O3, %≥60≥65≥70≥75
SiO2, %≤35≤33≤26≤24
Fe2O3, %≤1.0≤1.0≤0.6≤0.4
Apparent Porosity, ％≤17≤17≤17≤18
Bulk Density, g/cm3≥2.55≥2.55≥2.55≥2.55
Cold Crushing Strength, Mpa≥60≥60≥80≥80
0.2Mpa Refractoriness Under Load T0.6 ℃≥1580≥1600≥1600≥1650
Permanent Linear Change On Reheating,%
1500℃X2h		0～+0.40～+0.40～+0.40～+0.4
Thermal Shock Resistances 100℃ water cycles≥18≥18≥18≥18
20-1000℃ Thermal Expansich10-6/℃0.60.60.60.55
Thermal Conductivity (W/MK) 1000℃1.741.841.951.95