| 摘要 |
PROBLEM TO BE SOLVED: To obtain desirable shape, specific resistance value and, temperature coefficient, especially temperature coefficient actually near to zero by mixing at least one of metal or semimetal compounds to a specified composition in a ratio corresponding to desirable specific resistance, and baking such mixture at a temperature determined based on a desirable resistance variation ratio obtained from resistance value at room temperature and that at operating temperature. SOLUTION: A temperature determined based on a desirable resistance variation ratio is preferable to be 1700 deg.C or higher but 1800 deg.C or lower. As a composition, an organic substance showing a carbonizing yield of 5% or more by baking in an inert gas atmosphere is used. As metal or a semimetal compound, easily available metal carbide, metal boride, semimetal nitride, and semimetal oxide are listed. The kind and the amount of metal or semimetal compound used are suitably selected based on the resistance value and shape of an object heating element, alone or a mixture of two or more kinds can be used, but use of boron carbide, silicon carbide, boron nitride, and aluminum oxide is preferable from the standpoint of easy control of resistance value.
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