| 摘要 |
PROBLEM TO BE SOLVED: To sufficiently carry out nitriding at a lower temp. than a conventional method by calciningγ-Al2 O3 or its precursor to control its water content to a specified value or lower to obtainγ-Al2 O3 as an alumina and then heating the alumina in an ammonia gas containing hydrocarbons to nitride. SOLUTION: An alumina is heated and nitrided in a mixture gas of hydrocarbon gas and ammonia gas containing >=0.5 vol.% hydrocarbon gas to produce aluminum nitride. In this method,γ-Al2 O3 as an alumina prepared by calciningγ-Al2 O3 or its precursor to control the water content to <=1 wt.% is used. The heating temp. is specified to 1200 to 1700 deg.C. The calcining temp. is controlled to 600 to 1000 deg.C. Theγ-Al2 O3 includes various forms such as fibers, fine particles and flakes. It is preferable to use a basic aluminum chloride as a part or whole of the alumina source for theγ-alumina because the alumina shows good reactivity and formability.
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