What is High Alumina Brick?
High alumina brick refers to alumina with a content of more than 48% and less than 90%. It is made of refractory brick made of high alumina bauxite or sillimanite. The high alumina brick is usually divided into three according to the Al2O3 content in the product. The Al2O3 content of the first grade high aluminum product is 75%, the Al2O3 content of the second grade high aluminum product is 60-75%. the Al2O3 content of the third grade high alumina refractory brick is 48~60%.
The refractoriness of high alumina bricks fluctuates greatly. Most of the high alumina bricks have a load softening temperature greater than 1400 ℃. When high alumina bricks contain higher Al2O3, mullite and corundum, the thermal conductivity decreases with increasing temperature, but to 1000 Above ℃, the decrease is reduced. The chemical combination of high alumina brick has the characteristics of thermal shock stability and high normal temperature compressive strength, but its resistance to chemical attack is weak. High alumina bricks also have high high temperature creep rate. Generally, high aluminum bricks are composed of fine granular corundum, fine columnar mullite and glass phase. The glass phase is distributed between granular corundum. Under high temperature heat load, glass phase softening causes the squash corundum to slip and cause deformation. If a solid matrix is formed of mullite columnar crystals, the creep resistance can be relatively improved. However, in general, the creep rate of ordinary high-aluminum bricks at 1400 ℃and 0.2 MPa (50 h) is as high as 10% to 20%, and even large deformations often occur at a constant temperature of 50 h.
High Alumina Brick Applications
High alumina bricks are mainly lined in masonry rotary furnaces, steelmaking furnaces, glass furnaces
What is High Alumina Refractory Castable
The high alumina castable is a refractory castable prepared by adding a high alumina bauxite clinker as an aggregate and a powder, adding a binder and a dispersant. The integral lining refractory material can be directly cast or cast into refractory preforms for splicing. This series of refractory castables is mainly composed of refractory high alumina raw materials, using new micro powder technology and high efficiency composite chemical additives. The load softening temperature is high, the service life is long, and the construction is convenient. It has obvious effects on improving heat preservation, reducing heat energy loss and reducing environmental working temperature.
High Alumina Brick Applications
High alumina refractory castables are suitable for heating furnaces, soaking furnaces, heat treatment furnaces, rotary kiln, high temperature burner lining, heating furnace tube lining, refining equipment parts outside molten steel furnace and high temperature wear resistance of petrochemical catalytic cracking reactor lining,blast furnace tapping trough, iron furnace trough, iron powder pretreatment overall powder gun and other lining. High alumina brick can also be used to make large precast blocks and linings for quick construction.
