Corundum brick Features: Alumina content is higher than 90%. High compressive strength at
room temperature (up to 340MPa). High load softening starting
temperature (greater than 1700 ℃). Good chemical stability, strong
resistance to acidic or basic slag, metal and glass fluid, etc.
Corundum brick Advantages
1.high density& temperature resistibility
2. low bulk density, high compressive strength,
3. resistance to high temperature(≥1790℃)
4.good thermal shocking resistance
5.Excellent corrosion resistant to acids and alkalis
6. They are not influenced by H2, CO gases during use
It is divided into two kinds of corundum bricks, sintered corundum
brick and fused corundum brick.
Sintered Corundum brick is a refractory material with alumina
content higher than 90% and often containing trace impurity
elements Cr, Ti, Fe, and V. The corundum bricks on the market can
also be divided into these types according to the composition:
1. Brown corundum bricks are made of bauxite and coke (anthracite) as the main raw
materials. The main chemical components are alumina. The titanium
oxide ring contains a small amount of silicon oxide and iron oxide.
The micro hardness is HV1800-2200, and the toughness is higher than
SIC. High, the abrasive tool made of brown corundum is suitable for
grinding metals with high tensile strength, such as various general
steels, malleable cast iron, hard bronze, etc. It can also be used
to make brown corundum bricks, which is a kind of advanced
refractory material.
2. High-alumina corundum bricks are made of high-quality bauxite as the main raw material, and
sub-white corundum bricks are produced on the basis of high-quality
brown corundum bricks. Because its chemical composition and
physical properties are similar to white corundum, subwhite
corundum is produced on the basis of high-quality brown corundum.
Because its chemical composition and physical properties are
similar to white corundum, it is called sub-white corundum. Bulk
density≥3.8g/cm3, refractoriness≥1850℃. This product has the
hardness of white corundum bricks and the toughness of brown
corundum bricks. It is an ideal high-grade refractory and abrasive
material.
3. White corundum bricks are made by high temperature smelting with alumina powder as raw
material. White, harder than brown corundum The brick is slightly
higher and the toughness is slightly lower. Made into abrasive
tools suitable for the grinding of high carbon steel, high speed
steel and quenched steel. White corundum can also be used for
grinding and polishing materials, as well as precision casting
sand, spraying materials, chemical catalysts, special ceramics, and
advanced refractory materials.
4. Zirconium corundum brick is made by smelting alumina and zirconia as raw materials in an
electric arc furnace at a high temperature of over 2000℃. Tough
texture, dense structure and high strength. The main mineral phase
of zirconium corundum is a eutectic formed by a-alumina and
alumina-zirconia. In order to ensure the quality of zirconium
corundum, in addition to reasonable selection of smelting
parameters and processes, cooling processes and processing
techniques, it is also important to select appropriate additives to
reduce the silica content in zirconium corundum bricks, and to make
alumina and zirconia eutectic and have a uniform structure. The key
to the production of zirconium corundum bricks.
5. Chrome corundum bricks is a solid solution synthesized by high-temperature melting of
aluminum oxide and chromium oxide in a certain proportion. The use
of special refractory material production technology to make
refractory bricks can improve and enhance the internal quality of
the product and the high temperature performance of the product.
Fused corundum brick have 3 types: α-Al2O3, β-Al2O3 and α, β-Al2O3
fused cast corundum brick (fused cast corundum brick) refers to a
corundum refractory product made by fusion casting method with
corundum as the main crystal phase. Including α-Al2O3, β-Al2O3 and
α, β-Al2O3 3 kinds of corundum products composed of different
crystal phases. Among them, β-Al2O3 fused cast bricks, namely
Na2O·(11-12)Al2O3, contain about 5% Na2O. Fused cast corundum
bricks are composed of α-Al2O3 and β-Al2O32 crystal phases. about
the details we'll talk in fused corundum brick.