Periclase-forsterite refractories from silica magnesite

Conclusions

Periclase-forsterite refractories from silica magnesite of Beloretsk deposits are endowed with excellent properties.

The density of periclase-forsterite brick is subject to a wide range of changes depending on the grain distribution of the mixture, molding pressure, sintering temperatures and the introduction of additives. The effect of additives on the sintering of periclase-forsterite mixtures from silica magnesite has the same pattern as in the sintering of pure magnesium or regular magnesite. The most effective sintering additives are titanium and zirconium dioxides. Additions of ZrO₂ produces a higher refractoriness-under-load of periclase-forsterite brick.

Periclase-forsterite brick is highly-resistant in regenerator checkers of open-hearth furnaces. This is caused by peculiar changes in its mineralogical structure which occur during service, i.e. recrystallization of periclase in top layers which brings about higher density instead of looseness as in forsterite refractories bonded with unite.

The forming and the properties of periclase-forsterite refractories as they depend on such factors as basic raw material, manufacturing methods and phase composition need further studies and large-scale testing in order to determine the rational areas of application.