NOZZLE FOR CONTINUOUS CASTING AND METHOD OF PRODUCING THE SAME

摘要

A nozzle for use in continuous casting comprising an inner surface region defining the nozzle port for passing a molten steel, said inner surface region being formed from a mixture having a composition containing 50 to 80 wt% of boron nitride (BN) and 20 to 50 wt% of zirconium oxide (ZrO2), and a sintering assistant composed of silicon carbide (SiC) and boron carbide (B4C) mixed at a weight ratio of 1 : 1, the sintering assistant being added in amount of 5 to 10 wt parts to 100 wt parts of said mixture. The nozzle is produced by a process comprising the steps of: forming a uniform mixture of fine particles of boron nitride (BN), zirconium oxide (ZrO2), silicon carbide (SiC) and boron carbide (B4C); forming the mixture into a cylindrical blank;and fixing the cylindrical blank in the bore of a nozzle member by means of a joint filling material.