CRUCIBLE-PROTECTIVE SHEET AND METHOD FOR PROTECTING CARBONACEOUS CRUCIBLE USING SAID CRUCIBLE-PROTECTIVE SHEET

摘要

Provided are: pieces of crucible-protective sheet which have satisfactory handleabilty when laid and which can inhibit the conversion of the carbonaceous crucible into SiC from proceeding and thereby enables the life of the carbonaceous crucible to be prolonged; and a method for protecting a crucible using the protective sheet.The crucible-protective sheet (10) is interposed between a quartz crucible (4) in which a raw-material melt is to be contained and a graphite crucible (5) on which the quartz crucible (4) is to be placed. The crucible-protective sheet (10) comprises an approximately circular expanded graphite material and is composed of a plurality of protective-sheet pieces (11) obtained by dividing by at least one diametral line. In each cut surface (12) of each protective-sheet piece (11), an insertion slit (13) for connecting and fixing the protective-sheet pieces (11) to each other has been formed. The protective-sheet pieces (11) are connected and fixed to each other by engaging such insertion slits (13) with each other at at least two positions.