CARBON-CONTAINING MAGNESIA MATERIAL MONOLITHIC REFRACTORY

PROBLEM TO BE SOLVED: To produce a refractory excellent in corrosion resistance and fluidity, easy in cleaning of a kneading mixer, easy in hardening control and capable of suppressing a blister at the time of aging by adding a prescribed amount of sodium silicofluoride to a carbon-containing magnesia material monolithic refractory. SOLUTION: When the refractory is constituted with 0.5-5wt.% Al-Si alloy having 0.15mm grain size, 1-7wt.% silicon carbide, 0.1-2wt.% boron carbide, 1-10wt.% combination of more than one kind of pitch carbon starting material and carbon black, 0.05-1wt.% sodium silicofluoride as a binder and the balance magnesium based starting material, a hardened body which is hardly influenced by atmospheric temp. and stable as compared to a conventional hardened form is obtained. The alloy containing 12wt.% Si is used as the Al-Si alloy. The carbon black having >=0.1μm grain size is used, and the silicon carbide and the boron carbide are not restricted especially. A commercial product is used as the sodium silicofluoride. Seawater magnesia, etc., are used as the magnesia starting material.