| 摘要 |
PURPOSE:To prevent solidification of molten steel and sticking of alumina and make possible multiple times of casting by disposing a refractory material contg. a specific amount of boron nitride to a specific thickness on the inside wall surface of a nozzle for casting. CONSTITUTION:To prepare the titled nozzle 5-80wt% boron nitride powder and the residue graphite grains and alumina grains are compounded, and these are kneaded with a binder such as phenolic resin or pitch. At the time of rubber pressing this kneaded material, it is disposed to 3-15mm. thickness along the inside tube wall of the nozzle. Ordinary alumina-graphite type compound is disposed on the outside tube part and these are simultaneously molded to a molding. This molding is reduction-calcined to a product. With the resultant immersion nozzle, the wettability of boron nitride with molten steel and hot lubricity are provided in the part near the inside tube of the nozzle, and the nozzle for casting of outstanding nozzle clogging preventiveness is obtained. |
