화학공학소재연구정보센터
Journal of Materials Science, Vol.32, No.19, 5123-5126, 1997
Self-Propagating High-Temperature Synthesis of AlN in a Graphite Crucible in Air by Mechanical Activation
Powders of Al and C were mixed in a molar ratio of AI:C = 3:1 and were then ground in a planetary ball mill. When the thus mechanically activated mixtures were transferred into a graphite crucible and exposed to air, they spontaneously ignited and self-propagating high-temperature synthesis took place in two successive steps. The products were sliced along the depth direction and examined by X-ray diffraction. Depending on the depth of the crucible, aluminium nitride, aluminium carbide, aluminium oxynitride, aluminium oxycarbide and alpha alumina were detected. From measurements of the lattice constant, it was found that aluminium nitride with a 97% purity could be obtained at the bottom of the graphite crucible.