HIGH HEAT-RESISTANT MEMBER, METHOD FOR PRODUCING THE SAME, GRAPHITE CRUCIBLE AND METHOD FOR PRODUCING SINGLE CRYSTAL INGOT

摘要

A high heat-resistant member includes a graphite substrate including isotropic graphite and a carbide coating film including a carbide, such as tantalum carbide, and covering a surface of the graphite substrate, the carbide coating film having a randomly oriented isotropic grain structure in which crystallites having a size indexed by a full width at half maximum of a diffraction peak of an X-ray diffraction spectrum of not more than 0.2° from (111) planes are accumulated at substantially random. The orientation of the carbide coating film is determined by whether degree of orientation (F) in any Miller plane calculated based on an XRD spectrum using the Lotgering method is within a range from−0.2 to 0.2.