Papers by Author: Iman Farahbakhsh

Abstract: A nanostructured powder with uniform distribution of Ni and Cu powders was produced by means of the Ball Mechanical Alloying Treatment (BMAT). Mutual diffusion of Ni and Cu in the nanostructured layer and the microstructure of the cross section of the remaining powders were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Electron Probe Microanalyzer (EPMA). X-ray diffraction patterns revealed that increasing the milling time gives rise to decreasing crystallite size and lattice parameter during the MA process. Furthermore, scanning electron microscopy (SEM) was utilized not only for evaluating the morphology and microstructure of the remaining powder particles but also for proving this claim that during MA process, the mutual diffusion of Ni and Cu has occurred. Elemental mappings also show that the alloying process occurred in samples but obtaining the uniform shape, size and microstructure of the powder requires increase in the milling time.

Abstract: Mechanochemical process was applied for brass alloy production using chemical grade oxide powders. Alpha brass was produced when CuO, ZnO and PbO were milled under argon atmosphere in the presence of graphite (as reducing agent). Concurrent reduction of zinc, copper and lead oxides took place in the argon atmosphere, whereas the reactions of the reduction did not proceed well in the closed chamber that filled with air. These reactions were promoted by milling time up to 100 hours. The amount of reduction tends to decrease for longer times.