METHOD OF PRODUCTION OF REFRACTORIES APPLICABLE IN METAL CASTING Russian patent published in 1999 - IPC

FIELD: metallurgy. SUBSTANCE: the claimed method consists in preparation of fireproof component of refractory body for production of refractory which presents finely ground mixture of combined milling of alumina and silicon in ratio of 80:20-60:40. Then, mixture is prepared which contains the following amounts of ingredients, wt.%: grainy filler with content of Al₂O₃ above 98%, fraction 2-1 mm 20-28; fraction 1-0.5 mm 15-20; fraction 0.5-0 mm 12-18; graphite 3-8; fine ground mixture of combined milling of alumina and silicon in ratio of 80:20-60:40-30-38; and temporary binder above 100% 3-5. preparation is carried out as follows. Grainy filler with fractions 2-1 mm and 1-0.5 mm is poured into mixer, mixed, wetted with one half of temporary binder and mixed; preliminarily prepared mixture of combined milling of alumina and silicon is poured into mixer and mixed; molded products are dried to residual moisture content of not in excess of 0.5% and fired in reactive medium for, at least, 4 h. In so doing, the rate of temperature rise within interval of 1000-1400 C is not more than 50 C/h with, at least, one holding for, at least, 1 h. EFFECT: ecologically safe technology of manufacture of corundum-graphite refractories. 1 tbl