REFRACTORY ARTICLE AND METHOD OF MOULDING GLASS ARTICLES

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FIELD : chemistry. SUBSTANCE : invention relates to a refractory article used when moulding a glass article from glass mass based on an Al-Si-Mg system. The refractory article contains Al2O3 in amount of at least 90 wt % and a dopant which contains a rare-earth metal oxide, Ta, Nb, Hf or any combination thereof. The average grain size when sintering the article does not increase by more than 300%; the ratio of the geometrical dimensions of the grains is less than 4.0; the creep rate is less than about 1.0×10-5 mcm/(mcm×h). The refractory article can be made in the form of a refractory block or in the form of a glass mould with an overflow trough, which can be used when moulding a glass sheet. When the stream of glass mass based on the Al-Si-Mg system flows along the region of contact of the glass mould with the glass mass, a layer containing Mg-Al oxide is formed. EFFECT : reduced erosion of the glass mould and longer service life thereof in contact with molten glass. 9 cl, 6 tbl, 7 dwg