A comparison of different models for mechanical alloying

Five potential models describing the particle size distribution of powder during the mechanical alloying process have been analysed. The models are based on Smoluchowski's coagulation-fragmentation equations and use a range of size dependent aggregation and fragmentation rates. A technique has been developed to determine model parameters from the experimental average particle size. Size distributions predicted by these parameters compare well with the corresponding experimental results. The most successful models identify the most accurate size dependence. The numeric values of some aggregation and fragmentation rate parameters are qualitatively related to material properties of the initial powder charge. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.