Chromium corundum is primarily composed
of|??¨¬?¡§|-Al2O3-Cr2O3 solid solution, and the secondary 1 is fire-resistance
brick with little quantity of spinel (or no spinel) and Chromium Oxide,
which is only 1%-30% of all. The chromium corundum is two sorts, 1 casting
chromium corundum brick and the other sintering chromium corundum brick.
Usually, the chromium corundum brick is sintering chromium corundum brick. This
sort of brick is produced of|??¨¬?¡§|-Al2O3, adding correct amount of powder of
Chromium
Oxide and chromium corundum below the condition of high temperature. The
quantity of Chromium
Oxide in sintering chromium corundum brick is usually less than that in
casting 1. An additional technique to produce the chromium corundum brick would
be to adopt slip casting that the workers mix the|??¨¬?¡§|-Al2O3 powder with Chromium Oxide
uniformly, and add peptizer and organic binder until the state is thickened
slurry, meanwhile, they should add some chromium corundum into the thickened
slurry. After that the adobe may be formed and then sintered. (Chrome
Oxide Green Refractory )
The chromium corundum brick is utilized in
numerous fields such as the glass furnace lining, cover brick for drawing glass
flow hole and backing for hot metal pretreatment equipment, Waste incinerators,
and coal-water slurry gasifiers.
To inform the truth, chromium corundum can
be seen in many exhibitions because red corundum is primarily composed of
|??¨¬?¡§|- alumina, also known as chromium corundum, ruby. Now there is most
artificial red corundum in the marketplace. French chemist Framy fused the raw
material like pure aluminum powder, potassium carbonate, barium fluoride and
potassium dichromate for 8days in high temperature in crucibles to gain little
particles of ruby crystals, that is the beginning from the artificial ruby. In
1900, scientists have utilized melt aluminum oxide with adding a little
quantity of Ceramic
Color Pigment, Cr2O3, in proportion of 0.7%, to make out of 2g ~~ 4g ruby.
Now, it has been in a position to manufacture rubies and sapphires big enough
to reach 10g. There was some high-quality artificial ruby in Geneva and
Switzerland in 1885. It was said that the particles of ruby with potassium
dichromate that may increase the red effect, when the mixed products were
sintered in higher temperature, the high quality was exactly the same as
all-natural ruby. Nevertheless, that the artificial ruby could be produced in
large mode should be contributed to French chemist Verneuil. He produced the
artificial ruby officially in 1904, which is the milestone in the manufacture
history of ruby, chromium corundum. Due to the big scale of production, Chrome Oxide
Green Cr2O3 Pigment gradually
getting into the luxury fields.
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