Modeling of the planetary ball-milling process: The case study of ceramic powders

Abstract

A numerical dynamic-mechanical model of a planetary ball-mill is developed to study the dependence of process efficiency on milling parameters like ball size and number, jar geometry and velocity of the revolving parts. Simulations provide evidence of the correlation between milling parameters and the resulting microstructure of the ground material. In particular, maximum efficiency of the grinding process is observed with the most disordered ball motion, which is obtained within a well-defined range of jar to plate velocity ratios. As a significant case study in ceramic powder technology, the model is presented and validated for calcium fluoride (CaF2), ground under different conditions in a planetary mill, and then characterized by X-ray powder diffraction and scanning electron microscopy.