Influence of process control agent on interdiffusion between Al and Mg during mechanical alloying

The influence of a process control agent (PCA) on the reaction rate during mechanical alloying has been studied. Mechanical alloying of Al–Mg powder mixtures with different PCAs was carried out using a planetary ball mill. X-ray diffraction spectra showed that a small amount of PCA might lead to fast interdiffusion and reaction between Al and Mg although the crystalline sizes were in general the same for the powders when using different amounts of PCA. The fast interdiffusion and advanced reaction are closely associated with the diffusion distance between the powder particles due to the presence of PCA and to the actual weight ratio of ball to powder.