| 摘要 |
<P>PROBLEM TO BE SOLVED: To restrain the deterioration of a gas permeability characteristic after losing a silica, with respect to a refractory material having the gas permeability for continuous casting nozzle containing molten SiO<SB>2</SB>as a raw material having low expanding property. <P>SOLUTION: In the state of non-heating before using the permeable material composed of refractoriness aggregate, graphite, binder, etc., this refractory material is constituted of amorphous refractory aggregate containing 8-50 mass% SiO<SB>2</SB>component, wherein at least a part of the SiO<SB>2</SB>component has ≥0.1 mm grain diameter, and the quality of the material satisfies B/A≤4, wherein A represents room temperature permeability in the state of non-heating before using and B presents room temperature permeability after heating under reducing atmosphere at 1,550°C for 10 hr. Furthermore, for restraining the deterioration of the gas permeability characteristic according to losing of such amorphous molten SiO<SB>2</SB>, a filmy material composed of refractoriness material is formed around the gap in the portion becoming the gap after losing the molten SiO<SB>2</SB>. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
