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Mixtures of Al2O3, and C powders in a molar ratio of 1:3 were reduced in a N2 atmosphere. The effects of time, temperature, particle size of both reactants, and N2 flow rate were investigated. Kinetics show that the rate‐limiting process is the combustion of carbon, which leads to the reaction mechanism through the following basic steps: Al2O3= 2Al + 3/2 O2 3C + 3/2 O2→ 3CO (slow, with or without intermediate formation of CO2) 2Al + N2= 2AlN (fast) All of the experimental results have been discussed on the basis of this model, which allows one to predict the best conditions for preparing AlN powders.

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