| 摘要 |
This invention concerns a method for production of AlN powder. The reactants discovered in the invention are aluminum powder and a compound which contains NHx (e.g. NH2, NH3, NH4, N2H4, and N2H6 etc.) or halogens and which can be thermally decomposed or vaporized below the melting point of Al (660° C.). These two reactants are mixed at an appropriate ratio and then pressed into a compact with an appropriate shape. These two reactants, after being mixed at an appropriate ratio, may also be placed in a refractory container which has an opening at one end or has porous walls. In preparing the reactant compact or the reactant mixture, a dilutant such as AlN powder may also be added and mixed with the two reactants. This reactant compact or reactant mixture is then placed in a reaction chamber which is filled with nitrogen. By heating the reactant compact or the reactant mixture, the combustion synthesis reaction is ignited and AlN powder is produced. The compound decompress or vaporizes during being heated, thus creating numerous pores in the reactant compact or the reactant mixture. The nitrogen thus flows easily into the reactant compact(or the mixture) to react with Al. Besides, the halogen can catalyze the nitridation of Al and the NHx may attack easily the Al, thus promoting the reaction. AlN powder with high purity can therefore be produced under low nitrogen pressures (0.9-10 atm).
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