PURPOSE: To produce an inexpensive Cr crucible having excellent characteristics and suitable for melting oxides advantageously in industrial view points by casting chromium melt using a calcia mold.
CONSTITUTION: A calcia refractory material for calcia mold includes calcia, larnite, merwinite, anorthosite and CaO rich dolomite and the content of CaO is 40% or above, preferably 80% or above. A calcia refractory material having high CaO content react easily on an oxide or fluoride to absorb oxides and fluorides in Cr melt thus reducing the quantity of nonmetallic inclusions of oxide and fluoride significantly while exhibiting high stability against Cr or the like. Industrially pure Cr melt, e.g. electrolytic chromium melt having purity of 99% or above, is poured into the calcia mold preferably under vacuum or inert gas atmosphere of argon thus casting a crucible easily and precisely.
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Kamata, Kinya
Yoneda, Takashi
Kawae, Tatsuya