Understanding the crystalline phase formation in FeNi and AlNi binary alloy-nanoparticles produced by thermal plasma assisted gas phase condensation method

Abstract The paper addresses the issue of phase formation in the nano-crystalline binary alloys of Fe Ni and Al Ni, synthesized by plasma assisted vapor phase condensation process. In depth experimental analysis of the crystal structure, for the alloy nanoparticles with different compositions, is presented. The observed crystalline phases of the products have been compared with those expected from the standard phase diagram of the respective alloys. Crystalline phases of Fe Ni system showed no deviation, whereas, those of Al Ni showed considerable deviation. Differences in the thermo-physical properties of Al and Ni are shown to be responsible for such a deviation. The results are supported by a computational model, which accounts for the supersaturation of the species in gas phase, leading to nucleation and growth.