| Summary: | 碩士 === 國立成功大學 === 化學工程學系 === 87 === A new combustion synthesis （CS） process was developed for the production of Aluminum nitride powder. Sheet Aluminum powders mixing with or without NH4Cl or aluminum nitride were poured into a porous container made of Aluminum foil with one open end or coating a layer of aluminum nitride inside the Aluminum foil before pouring the reactant. The container was then placed in a stainless reactor filled with nitrogen pressure around 1-5 atm. A combustion synthesis reaction was ignited by heating the top surface of reactant powders and the heating power was about 1200W~1800W. Then, the reactant converted to Aluminum nitride, and a high product yield was achieved about 95% under above condition. In this experiment, several experimental parameters affecting the combustion synthesis reaction and product yield were investigated, e.g. The addition content of NH4Cl, aluminum nitride and mixtures of above two components, the morphology or dimension of container, the packing density of Aluminum powders, and pressures of surrounding nitrogen gas.
In the consequence of experiments, we found that：（1）when the reactant was only composed of pure Al powders, the porous container must be coated with aluminum nitride powders along the container firstly about 5 ~ 10㎜ thickness, before pouring the Al powders. （2）the optimum weight ratio of addition of NH4Cl is about 0.5% ~ 1%.（3）the optimum weight ratio of Al：AlN is about 1：1 and AlN with large particle size distribution favors the combustion reaction than fine AlN powders.
In addition, at high packing density, the product yield is not good, and increasing the surrounding N2 pressure could increase product yield.
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