The refractoriness of both soil and silicon of the high-alumina brick with dead burned magnesite should be higher, and the refractory material should be more resistant. Because of the high Al2, low amount of waste, and the formation of less meltable vitreous body, the softening temperature under load is higher than that of the clay brick. However, the softening temperature under load is still lower than that of the silica brick due to the lack of mesh structure formed by mullite crystallization.
There are more Al2O3 in the high-alumina brick with dead burned magnesite, which is close to the neutral refractory material and can resist the erosion of acidic slag and alkaline slag. Due to the SiO2 contained in it, the ability of alkali slag is weaker than that of acid slag.
The dead burned magnesite is mainly used for laying blast furnace, electric furnace top reflector, in addition, the high alumina brick is widely used as open hearth regenerative grid brick, plug head for pouring system, nozzle brick and so on. But the price of high alumina brick is higher than that of clay brick, so it is unnecessary to use high alumina brick where the clay brick can meet the requirements.
Silica brick belongs to the acid resistance, so the slag erosion resistance ability, the weak alkaline corrosion resistance, high refractoriness is a brick, high refractoriness under load, almost close to the refractoriness, generally above 1620 ℃, this is the advantage of silica brick, thermal stability, water cooling times only 1 ~ 2 times, this is mainly because there are Gao Dixing crystal change's sake, so you should not have radically for temperature silica brick.