Kinetics of amorphization processes by mechanical alloying: A modeling approach

In mechanical treatments by ball milling, the mechanical energy is transferred to powders when these are trapped between colliding milling tools. Under such processing conditions, the number of collisions is therefore the natural quantity to which refer the kinetics of any given transformation. A statistical model is here developed to relate the transformation rate to the amount of powder trapped at each collision. The phenomenological model is applied to mechanically induced amorphization processes of intermetallic compounds and binary mixtures. Provided that accurate experimental methodologies are employed to estimate the amorphization rate and the number of collisions, the comparison between experimental and theoretical kinetic curves permits to obtain a deeper insight into the observed kinetic behavior.