Combustion Synthesis of Aluminum Nitride Particles and Whiskers


  • Z. A. Munir—contributing editor

  • Based in part on the thesis submitted by author JLS for the M.Ing. Degree in Chemical Engineering, University of Stellenbosch, Stellenbosch, South Africa, 1997.


Aluminum nitride (AlN) was produced via the combustion synthesis of loosely packed aluminum powder (pore fraction of ∼0.8) in a graphite reactor that was lined with permeable carbon felt. Almost-complete conversion was achieved with a forced flow of nitrogen for beds 50-150 mm deep (mass of 200-650 g). The product was in the form of a loosely aggregated bed, with regions of distinct morphology, and had a predominantly whisker morphology. Some control over the microstructure was possible by changing the processing parameters. The addition of 5% of ammonia to the nitrogen resulted in a uniform production of whiskers, whereas a 50% solid-phase dilution with AlN favored the production of particles.