REFRACTORY FOR CASTING RARE EARTH ALLOY AND METHOD FOR PRODUCING THE SAME AND METHOD FOR CASTING RARE EARTH ALLOY

摘要

In casting a rare earth alloy into a sheet (6) using a tundish (3, 13), as a refractory for a tundish which can be used for dispensing with a preheating step for the purpose of improving the flow of a melt (2), use is made of a refractory which consists substantially of 70 wt.% or more of Al2O3 and 30 % or less of SiO2 or consists substantially of 70 wt.% or more of ZrO2 and 30 % or less of one or more of Y2O3, Ce2O3, CaO, MgO, Al2O3, TiO2 and SiO2, and has a bulk density of 1 g/cm<3>, a thermal conductivity in a temperature range of 1200 to 1400 DEG C of 0.5 kcal/(mh DEG C) or less, and a heat loss under a heating condition of one hour at 1400 DEG C of 0.5 wt.% or less.