ON TEMPORAL VARIATIONS IN THE GRANULOMETRIC CHARACTERISTICS OF BINARY MIXED MICROPOWDERS TREATED IN A PLANETARY-TYPE BALL MILL

Abstract

Integral and differential particle size distribution functions have been experimentally determined for two-component mixed micropowders, which contain stoichiometric amounts of polycrystalline aluminum, nickel, and titanium, as well as amorphous boron, and have been mechanically treated in a planetary-type ball mill under different time conditions of the process. The influence of the duration of treatment of the above mixtures on the mathematical parameters of the found distribution functions has been analyzed. It has been shown that, in all considered cases, these functions can be represented in a lognormal form. The most informative statistical characteristics (moments) of these functions have been determined. The dependences of these characteristics on the duration of the mechanical treatment of the mixtures have been revealed. Within the framework of an approximation based on the use of generalized dynamic-stochastic Langevin-type equations, a kinetic model has been proposed for the process of mechanical treatment of metallic and non-metallic mixed micropowders in planetary-type mills. The model makes it possible to describe, as a first approximation, the temporal evolution of the fractional composition of the mixtures during their machining, as well as to record temporal variations of the main statistical characteristics of the corresponding distribution functions in this process.