Refractory Technology
Carbon refractories

Do not burn/oxidise, when exposed to air on heating
Do not resist temperature fluctuations
Are not attacked by slags, as they are not wetted by melts
Have extremely low thermal & electrical conductivities

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Refractory Technology
Silica refractories

All of these
Can not be used in the dome of hot blast stoves
Have lower thermal conductivity than fireclay bricks
Crack when subjected to sudden change of temperature

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