Synthesis and consolidation behavior of Al/AIN composite powders by reactive RF thermal plasma spraying

Al/AlN composite powders were synthesized using a new technique based on reactive RF thermal plasma spraying, and an investigation of the microstructure and consolidation behavior of the synthesized Al/AlN composite powders revealed that the volume fraction of the AlN particles was higher on the outer layer. Numerous nano-particles were attached to the surface of the Al/AlN composite powders, and the effects that the nanoparticles had on the consolidation of the Al/AlN composite powders are discussed herein. The attached nanoparticles acted as a compaction activator, filling the vacant space among the Al/AlN composite powders during compaction. The as-sprayed and sintered powder compact had a higher hardness value than the ultrasonicated and sintered powder compact due to a lower porosity in addition to the presence of hard AlN nanoparticles. (C) 2015 Elsevier B.V. All rights reserved.