Abstract: A configuration in which particles of pitch 2 having a softening point in the range of 70 to 200° C. and a diameter equal to or smaller than 30 ?m are held on the surfaces of particles of a refractory raw material 3 having a diameter equal to or smaller than 50 ?m is employed. This pitch-containing refractory raw material 1 can be used with the pitch being in a fine-particle form without any aggregation even after the long-term storage. Using it as a part of a raw material formulation allows the fine particles of pitch to be uniformly dispersed during the mixing or kneading process. The resulting carbon-containing refractory has an excellent corrosion resistance. It also provides suppressed increase in the Young's modulus while maintaining the level of strength, thereby being excellent in thermal spalling resistance even with the carbon content ratio being low.

Abstract: A configuration in which particles of pitch 2 having a softening point in the range of 70 to 200° C. and a diameter equal to or smaller than 30 ?m are held on the surfaces of particles of a refractory raw material 3 having a diameter equal to or smaller than 50 ?m is employed. This pitch-containing refractory raw material 1 can be used with the pitch being in a fine-particle form without any aggregation even after the long-term storage. Using it as a part of a raw material formulation allows the fine particles of pitch to be uniformly dispersed during the mixing or kneading process. The resulting carbon-containing refractory has an excellent corrosion resistance. It also provides suppressed increase in the Young's modulus while maintaining the level of strength, thereby being excellent in thermal spalling resistance even with the carbon content ratio being low.

Abstract: Disclosed herein are a refractory material of high-purity electrofused magnesia clinker having good resistance to corrosion by slag, especially the slag with a high iron content, at high temperatures under an oxidative environment, and a burned or unburned refractory brick made of such refractory material of high corrosion resistance, which is superior in corrosion resistance as well as spalling resistance.The refractory material comprises more than 10 wt. % of electrofused magnesia clinker containing 98.0 to 99.8 wt. % of MgO, less than 0.05 wt. % of SiO.sub.2, and 0.1 to 2.0 wt. % of CaO. It may be in the form of burned or unburned or prepared unshaped refractories.

Abstract: Erosion or corrosion that has been caused during pouring a molten steel through a sliding gate nozzle for continuous casting becomes very serious when a specially treated molten steel such as deoxidized steel with a Ca alloy is applied for continuous casting. Such erosion can be eliminated by partially arranging a zirconia base refractory material on a portion of the inner surface of the nozzle hole. The zirconia base refractory material is composed of more than 53% by weight of partially stabilized zirconia base refractory material having less than 10 mesh grain size, 1 to 7% by weight of metallic silicon powder having less than 100 mesh grain size and 3 to 10% by weight of carbon powder.

Abstract: Alumina-carbon-based refractory plates for the sliding nozzle are produced from alumina powder and carbon powder of specific particle diameter, in addition to the conventional refractory materials. The plates are durable and have good resistance to molten steel because of a compact structure which prevents the sticking of molten steel.