A combined experimental and theoretical investigation of the Al-Melamine reactive milling system: A mechanistic study towards AlN-based ceramics

Abstract

A versatile ball milling process was employed for the synthesis of hexagonal aluminum nitride (h-AlN)<br><br>through the reaction of metallic aluminum with melamine. A combined experimental and theoretical<br><br>study was carried out to evaluate the synthesized products. Milling intermediates and products were<br><br>fully characterized via various techniques including XRD, FTIR, XPS, Raman and TEM. Moreover, a<br><br>Boltzmann distribution model was proposed to investigate the effect of milling energy and reactant<br><br>ratios on the thermodynamic stability and the proportion of different milling products. According to the<br><br>results, the reaction mechanism and milling products were significantly influenced by the reactant ratio.<br><br>The optimized condition for AlN synthesis was found to be at Al/M molar ratio of 6, where the final<br><br>products were consisted of nanostructured AlN with average crystallite size of 11 nm and non-crystalline<br><br>heterogeneous carbon.