Since it has a low content of periclase and high content of magnesia-chrome spinel and magnesium ferrite, and its eutectic compounds have a low melting point, it has a lower refractoriness than magnesia brick, generally only 1850 -1960℃.
The periclase and magnesia-chrome spinel in the magnesia chrome brick can form a network sketeton. Since there are only a few low-melting substances filled in the network gaps, when subjected to high temperature loads, although the low-melting material is softened, the network skeleton can still support the load. Therefore, its softening temperature under load is higher, generally above 1550℃. The refractoriness is lower than that of magnesia brick.
It has a high content of magnesia-chrome spinel and magnesium ferrite and a lower linear expansion coefficient. Meawhile, the porosity of magnesia chrome brick is higher than that of magnesia brick, so it has good thermal stability.
It has a low content of calcium forsterite, so it is not easy to generate anisotropy expansion stress in it. Magnesium ferrite spinel is dissolved in the magnesia-chrome spinel and has a high solubility and wide dissolution temperature range, so the precipitation and dissolution of magnesium ferrite will not produce a large stress. Therefore, it has good thermal shock resistance and its water-cooled frequency is up to about 25 times.
Magnesia chrome spinel is the compound of magnesium oxide and chromium oxide and chromium oxide is typical of neutral oxide, so it has a strong corrosion resistance to both alkaline and acidic slag.
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