Abstract
This paper investigates the rheological properties and extrusion behavior of kaolin pastes with varying water content to enhance their applicability in 3D printing.Employing the Bulkley-Herschel-Papanastasiou model, we analyze the flow characteristics of these pastes, revealing that water content significantly influences yield stress, viscosity, and flow index.Experimental results show that decreasing water content increases both yield stress and viscosity, indicating higher resistance to deformation in pastes with lower water content.This contributes to mechanical stability but also presents challenges during extrusion due to increased pressure requirements.Optimal water content ranges (52.5%-55%) are identified.Kaolin pastes within these ranges exhibit desirable mechanical extrudate properties suitable for 3D printing.In contrast, pastes with lower water content (50%) face significant extrusion challenges such as material segregation and high extrusion pressures.Finite Element Method (FEM) simulations accurately predict experimental results for extrusion of pastes with moderate water contents but show deviations at lower water contents, indicating a need for further refinement of the numerical model.This research provides essential data for optimizing and refining 3D-printing process parameters.The findings will contribute significantly to the advancement of additive manufacturing, enabling the fabrication of high-performance 3D-printed structures with enhanced mechanical properties and durability.