Different refractory brick for short. Heterotypic brick can be divided by preparation methods to differentiate burnt brick, air brick, fused brick (fused cast brick), refractory insulating brick; , heterotypic brick according to the shape and size can be divided into standard brick, ordinary brick, type, etc. Heterotypic brick kiln can be used as a building and high temperature thermal technology equipment of construction materials and structural materials, different firebrick and can withstand various physical and chemical changes in the heat and mechanical action.
Such as refractory clay bricks, high alumina brick, silica brick, magnesite brick, etc.
Heterotypic brick, its main characteristic is high early strength, 3 to 7 days maximum compressive strength at room temperature can reach more than 30 mpa, the disadvantage is that the temperature, volume stability, strength is reduced, the biggest drop of about 40%, so for room temperature compressive strength must meet the design and the requirement of national standard. With the decrease of strength of temperature is the main factor: deformed low calcium and high aluminum refractory cement during the process of heating oven temperature reaches a certain temperature (350 ℃), the natural gas hydrates to dehydration, conversion of natural gas hydrates cement structure, density and intensity is reduced, castable volume changes, the castable body strength fell to the lowest point, after stabilization.
With heating temperature rise to 1100 ℃, the cement sintering gradually, heterotypic brick began to convert mullite crystal crystal shape. With temperature rising, mullite crystal growing, castable in liquid state, substrate glass phase in the formation of high temperature ceramic sintering, strength improved significantly. At 1300 ℃ or so, the strength of the brick body can reach more than 60 mpa, which is a significant characteristics of different refractory high temperature condition.