To impart resistance to cracks and oxidation and to prevent molten liquid from contamination caused by mixture of Si and Fe by kneading a mixed powder having a specific composition comprising a graphite powder, a boron carbide powder and a glass powder free from Si and Fe components, then forming and firing the formed body.
A graphite containing refractory for melting high purity aluminum is obtained by kneading a mixed powder comprising 10 to 70 wt.% graphite powder, 10 to 50 wt.% boron carbide powder and 5 to 30 wt.% glass powder free from Si and Fe components, then forming and firing the formed body. The graphite powder is produced from natural graphite or artificial graphite. As the raw material of glass powder free from Si and Fe components, glass comprising Na2O-B2O3-CaO-Al2O3 or the like is suitable. It is possible to add an oxide powder such as Al2O3, MgO and ZrO2 free from Si and Fe or a non- oxide powder such as BN, AlN and ZrB2 free from Si and Fe to the mixed powder.
HAMADA YOSHIAKI
NAKAGAWA MASAO
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