Approach to structural anisotropy in compacted cohesive powder

We investigate the mesoscopic regime between microscopic particle properties and macroscopic bulk behavior and present a complementary approach of physical experiments and discrete element method simulations to explore the development of the microstructure of cohesive powders during compaction. On the experimental side, a precise micro shear tester $$(\mu \hbox {ST})$$(μST) for very small powder samples has been developed and integrated into a high resolution X-ray microtomography (XMT) system. The combination of $$\mu \hbox {ST}$$μST and XMT provides the unique possibility to access the 3D microstructure and the particle network inside manipulated powder samples experimentally. In simulations we explore the structural changes resulting from compaction: a Hertzian contact model is utilized for compaction of an isotropic initial configuration created by a geometrical algorithm. As a first result of this approach we present the analysis of the compaction of slightly cohesive $$\hbox {SiO}_2$$SiO2 particles with special regard to bulk density, heterogeneity, compaction law and structural anisotropy.

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