| 摘要 |
PROBLEM TO BE SOLVED: To provide a graphite crucible so designed that the cylindrical portion thereof is constructed of longitudinally plurally divided members and both the upper part and lower part of the cylindrical portion are respectively fitted with such rings of carbon fiber-reinforced carbonaceous material that each of their inner diameters becomes nearly equal to the outer diameter of the cylindrical portion when a stock is melted to enable a quartz crucible disposed inside the cylindrical portion to be used repeatedly. SOLUTION: This graphite crucible 1 so designed as to hold a quartz crucible 6 inside which a stock is to be melted and also designed to be supported externally is made up of a cylindrical portion 2 and the bottom 3, wherein the cylindrical portion 2 is constructed of longitudinally divided cylindrical members 2a, 2b in two or three portions. Both the upper and lower parts of the cylindrical portion 2 are respectively fitted with rings 4, 5 of carbon fiber-reinforced carbonaceous material equal in thermal expansion coefficient to quartz so that the outer diameter of the cylindrical portion 2 becomes nearly equal to each of the inner diameters of the rings 4, 5 when a stock in the quartz crucible 6 is melted. Besides, the outer diameter of the cylindrical portion 2 at a site above that fitted with the lower part ring 5 is made smaller than that at the site fitted with the ring 5 so as to facilitate the attachment/detachment of the crucible 1 after cooled.
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