An innovative setup to study the breakage of SiO2 agglomerates under shear stress

Granular materials are involved in many industrial processes such as mixing, compaction, etc. When the granular material is in the form of agglomerates, i.e. an assembly of aggregates, particle fragmentation might occur under shear stress. This can either be a benefit for the process and should be controlled, or an issue which must be avoided. This paper focuses on the study of agglomerate breakage under shear stress, presenting a new experimental set-up designed for industrial contexts. The stress range selected lead to two distinct regimes: at low stresses, agglomerates break into individualized fragments, while high stresses fines agglomeration leads to the formation of flakes. These observations contribute to quantify the breakage stress of initial agglomerates, showing agreement with findings in the existing literature. • Innovative device for characterizing controlled sheared granular materials. • Particle Size Distribution mode decomposition analysis. • Scanning Electron Microscopy. • Tribological in situ force measurements. • Fragmentation and reagglomeration of SiO 2 powder.