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REFRACTORIES
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Refractrory materials are those materials, which retain their stability
at high temperatures. ASTM C71 refractories defined as
„non-metallic materials with chemical and physical properties,
allowing them to use for such structures, systems or components which are exposed to conditions above 500 °C“.
Refractories must be chemically and physically stable at
high temperatures. Depending on the environment should be resistant to thermal shock, chemically
inert or have a specific range of thermal conduktivity and coefficient of thermal expansion.
Aluminium oxides (Al2O3) is
one of the most important materials used for manufacturing
refractories. Some applications require a special refractories. One of
them is silicon carbide, which is used in very difficult conditions.
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Refractory producer, refractory special-shape and refractory-cement our company delivers:
a. aluminium oxides Al2O3 in various fractions and
packaging
b. silicon carbide SiC
c. composite refractories: in such proportions and mixed fractions SiC and Al2O3
d. chromium oxide Cr2O3
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Use of refractory materials
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production of iron and steel
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70 %
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ceramic industry
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6 %
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industry of non-ferous metals
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3 %
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glass industry
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4 % |
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cement industry
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7 %
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chemical industry
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4 %
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other
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6 %
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Chromium oxide Cr2O3 |
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enlarged 1000 x
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Chromium oxide Cr2O3 is very
resistant to high temperatures, the temperature of melting is
2275 ° C, it is important refractories, which is used among
others in the productions of
special refractory bricks. They are made from either pure
chromium oxide or is supplemented by other more refractory
materials, especially silicon carbide SiC or aluminium oxide
Al2O3.
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Chromium oxide Cr2O3
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TEMPERATURE OF MELTING |
Silicon carbide (SiC)
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2730
°C |
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Aluminium oxide (Al2O3)
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2072
°C |
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Chromium oxide (Cr2O3)
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2275
°C
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