| 摘要 |
PROBLEM TO BE SOLVED: To improve the spalling resistance by using a porous refractory not containing carbon at a part of a submerged nozzle in contact with the molten steel to suppress oxidation of carbon in the refractory to constitute a nozzle body by the oxygen in the molten steel during the casting. SOLUTION: A surface of a part of a submerged nozzle in contact with the molten steel is covered with the porous refractory made of carbide and/or non-oxide. The porous refractory is 20-60% in apparent porosity, 0.02-0.5mm in mean diameter of pores, and 2-10mm in covering thickness. The conventional method such as the mechanical forming method, the rubber press method, and the slip cast method can be used as the manufacturing method of the submerged nozzle. The binder to be added which is required during the manufacture is not specially limited, and the binder such as the sodium silicate, aluminum phosphate, phenol resin, and CMC may be accepted. |
