The main mineral
composition of Chromium corundum is -Al2O3-Cr2O3
solid remedy. The secondary mineral composition is a little volume of composite
spinelle (or composite spinelle -free), and also the refractory bricks whose
chromium oxide content is 1% ~ 30%. You can find two types: cast chrome
corundum brick and sintered corundum brick.
In general, the
chromium corundum brick refers towards the sintered chrome corundum brick. It
utilizes |¨¢-Al2O3 as raw material, being added the correct volume of chromium
oxide powder and fine powder of Chromium corundum clinker, right after getting
molded and burnt at higher temperature. Chromium oxide content material of
sintered chrome brick is usually decrease than that in the cast chrome corundum
brick. You'll be able to also use mud casting method to have a preparation,
uniformly mixing alpha-Al2O3 powder and chromium oxide powder, adding
resolution adhesive agent and organic bonding agent to create thick mud,
although adding some chromium corundum clinker, utilizing grouting method to
make unfired bricks and burn them. It may be utilized because the glass furnace
lining, plate brick of wire drawing glass flow liquid hole cover and utilized
for hot metal pretreatment device, garbage incinerator, coal slurry pressurized
gasification furnace backing, etc.
What steps do we
have for the selection principles of chrome corundum?
1. Fundamental
Refractory uses magnesium Oxide and calcium oxide as the main elements, what's
frequently utilized is magnesium brick. Magnesia brick containing Magnesium
Oxide more than 80% to 85%, possessing very good resistance around the
fundamental slag and iron slag, whose refractoriness is greater than that of
clay brick and silica brick, is mostly used in open hearth furnace, oxygen
converter, electric furnace, non-ferrous metal smelting equipment and high
temperature gear.
2. Neutral
refractory materials use aluminum oxide, chromium oxide or carbon as principal
components. Alumina merchandise containing greater than 95% of alumina are a
kind of top quality refractory materials. Chrome brick utilizing chromium oxide
because the main component has very good corrosion resistance to steel slag,
but the poor heat shock resistance, lower higher temperature load deformation
temperature. Carbonaceous refractory has carbon brick, graphite and silicon
carbide products, whose coefficient of thermal expansion is quite low, having
high thermal conductivity, heat vibration performance, high strength at high
temperature, acid and alkali and salt corrosion, without any wetting from metal
and slag, and soft lightweight. It?¡¥s widely employed as a high-temperature
furnace lining supplies, also as petroleum, chemical lined autoclave.
3. Acid
refractory material uses silicon oxide because the principal element and what
we frequently use is silica brick and clay brick. Silica brick is siliceous
merchandise containing silicon oxide above 93%, and the employed material is
silica stone, waste silica brick and so on, whose anti-acid slag has a robust
erosion capability, higher load softening temperature, and whose volume will
not shrink soon after repeated calcination, as well as a slight expansion.; but
it?¡¥s vulnerable to the erosion of simple slag, using a poor thermal shock
resistance. The silica brick is primarily utilised in the thermal equipment
such as coke oven, glass furnace, acid furnace and so forth. Clay brick makes
use of refractory clay because the major raw material, containing 30% to 46%
alumina, and belongs to a weak acid refractory and fine heat shock resistance,
getting a corrosion resistance against acid slag, so it features a wide range
of applications.
4. In specific
occasions, the used chrome corundum has high temperature oxide components, such
as alumina, lanthanum oxide, beryllium oxide, calcium oxide, zirconia, etc.,
and a few refractory compounds, like carbides, nitrides, borides, silicides and
sulfides; and high temperature composite components, such as metal ceramic,
higher temperature inorganic coatings and fiber reinforced ceramics. Generally
in the market, we are able to typically see Cr2O3?¡éCr2O3
compound, sometimes even Cr2O3 99% and Chrome Oxide
Green Powder.