EXPANDABLE GRAPHITE SHEET, METHOD FOR PROTECTING CARBONACEOUS CRUCIBLE USING THE EXPANDABLE GRAPHITE SHEET, AND SINGLE CRYSTAL PULLING APPARATUS

摘要

This invention provides an expandable graphite sheet having improved tensile strength. There are also provided a method for protecting a carbonaceous crucible, which can realize significant shortening of working time and, at the same time, can cover the internal surface of the crucible without any space and breaking of the sheet and is also suitable for increasing the size of the crucible, and a single crystal pulling apparatus, by using an expandable graphite sheet having improved tensile strength as an insole in a carbonaceous crucible. An expandable graphite sheet (10) is characterized in that a reinforcing material (12) formed of a carbon fiber is formed in a laminate form on at least one side of a base material (11) formed of an expandable graphite material. Further, it is characterized in that the expandable graphite sheet (10) is interposed between the quartz crucible and the carbonaceous crucible in which the quartz crucible is mounted, for use of the expandable graphite sheet (10) as an insole for covering the internal surface of the carbonaceous crucible.