Thixotropic spectra and Ashby-style charts for thixotropy

There is no universal model for thixotropy, and comparing thixotropic effects between different fluids is a subtle yet challenging problem. We introduce a generalized (model-insensitive) framework for comparing thixotropic properties based on thixotropic spectra. A superposition of exponential stress modes distributed over thixotropic time scales is used to quantify buildup and breakdown times and mode strengths in response to step-change input. This mathematical framework is tested with several experimental step-shear rate data on colloidal suspensions. Low-dimensional metrics based on moments of the distribution reveal characteristic average thixotropic properties, which are visualized on Ashby-style diagrams. This method outlines a framework for describing thixotropy across a diverse range of microstructures, supporting scientific studies as well as material selection for engineering design applications. (C) 2022 The Society of Rhealogy.

Automated summary

This paper introduces a generalized framework for comparing thixotropic properties between different fluids. By analyzing thixotropic spectra and using a superposition of exponential stress modes, the response of fluids to step-change input can be quantified. Low-dimensional metrics and visualization reveal characteristic average thixotropic properties. This framework can describe thixotropy in a diverse range of microstructures and support material selection in scientific studies and engineering design applications.