Unraveling the Effects of Process Control Agents on Mechanical Alloying of Nanostructured Cu-Fe Alloy

Nanostructured Cu-20Fe alloy was synthesized by mechanical alloying process and the effects of process control agents (PCA) on the phase formation, crystallite refinement and morphology of powder particles were studied. The dissolution of Fe into Cu matrix and the morphology of powder particles were analyzed by X-ray diffraction (XRD) technique and scanning electron microscopy (SEM), respectively. The mean crystallite size was approximated by the method developed by Williamson and Hall. It was found that in the absence of PCA (Toluene in the present work), the iron peaks vanish after 5 h of mechanical alloying process and the mean crystallite size of the matrix decreases to 35 nm and large agglomerated particles are formed during milling. In this regard, it was found that the addition of PCA decreases the rate of crystallite refinement and formation of solid solution but does not affect the final mean crystallite size. It was also found that the addition of PCA during milling decreases the powder particle size considerably and by preventing agglomeration can lead to a finer powder particle size compared with the initial unmilled powders. It was also revealed that the effect of PCA on particle size is much greater than the effect of milling time.