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arXiv · 2207.02720

Rheology of Polydisperse non-Spherical Graphite Particles Suspended in Mineral Oil

Th. Larsen·A. L. Søbye·J. R. Royer·W. C. K. Poon·T. Larsen·S. J. Andreasen·A. D. Drozdov·J. D. C. Christiansen
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Abstract

We study the role of filler concentration and microphysics on the rheology of polydisperse flake-graphite particles suspended in Newtonian mineral oil. Under steady shear, our samples exhibit shear thinning and yielding behaviour is observed for volume fractions $ϕ> 0.18$. Time-temperature superposition was observed using an Arrhenius-type horizontal shift factor, giving a flow activation energy that is dependent on the graphite volume fraction, suggesting concentration-dependent contributions to relaxation processes in the suspensions. The flow curves are fitted by a constraint-based model, indicating that the flow behaviour is controlled by frictional and adhesive contacts, with the model suggesting that the adhesive stress is temperature dependent.

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Th. Larsen, A. L. Søbye, J. R. Royer, W. C. K. Poon, T. Larsen, S. J. Andreasen, A. D. Drozdov, J. D. C. Christiansen. 2022-10-26. Rheology of Polydisperse non-Spherical Graphite Particles Suspended in Mineral Oil. https://doi.org/10.1122/8.0000511

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