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A new simulation scheme for tape casting is presented and applied. The model allows considering both the macroscopic flow behavior and the orientation of individual particles inside the ceramic slurry. It is based on the smoothed particle hydrodynamics method, a particle‐based computational fluid dynamics solver, and Jeffery's equations of particle motion, which describe the rotation of rigid, ellipsoidal particles in a fluid. It is shown how different process parameters and the rheological behavior of the slurry influence its flow behavior, which in turn affects the orientation of nonspherical particles inside the slurry. The simulations predict that a preferred, anisotropic particle orientation develops in the green tapes, whose extent depends mainly on the powder properties. All simulations are performed with real tape‐casting data concerning geometry of casting unit, casting parameters, slurry rheology, and powder properties. The anisotropy results are confirmed by experimental analysis of cross sections of tape‐cast films made from different powders.

Dimensional control is one of the basic problems in ceramic processing, especially for tape cast ceramic sheets which are used to build up multilayer structures for high-integrated components. Uncontrolled anisotropic shrinkage can cause geometrical distortion and circuit failure of multilayer ceramics during sintering. The understanding of the relationship between green tape microstructure and shrinkage anisotropy is of great importance for further miniaturization of multilayer devices. In this study, alumina powders with spherical particle shape were used to cast green tapes. The microstructure as well as the pore orientation and the shrinkage behavior were analyzed. According to the sintering theory, grain growth and pore elimination are the two most important mechanisms to describe sintering shrinkage. In this work, three-dimensional shrinkage behavior of tape cast alumina powders with spherical particle shape was investigated and correlated with pore orientation in the microstructure. Specifically, the reason for the different shrinkage in z-direction compared to the lateral shrinkage is in focus. The study is based on experiments as well as on mathematical visualization.

In this paper an approach for the numerical modeling of particulate suspensions is illustrated, its implementation described and its application investigated. The numerical fluid model is based on the smoothed particle hydrodynamics (SPH) method. The suspended solids are modeled as clusters of SPH particles using a rigid body motion solver. Two different SPH formulations for the viscous stress are applied and their characteristics are compared. The influence of numerical and physical parameters on the viscosity of the system is analyzed. The rotational motion of suspended solids under shear as well as the dependency of the viscosity on the solid volume fraction is investigated and compared to analytical models. Guidelines for SPH suspension simulations are derived aiming at the minimization of numerical errors

In this study, the influence of the shape of the doctor blade on the flow inside the tape casting unit and on the resulting tape properties is investigated both numerically and experimentally. Using the results from the analysis of the produced tape and from the simulations of the flow inside the tape casting unit, the relationships between blade geometry and the particle orientation in the resulting tape, as well as the resulting tape thickness, are shown. Additionally, the experimentally and numerically obtained results were compared to an analytical model for the prediction of the tape thickness. The simulations were carried out using the particle-based smoothed particle hydrodynamics method using a non-Newtonian fluid model to describe the ceramic slurry. Both in experiment and simulation, the influence of the blade geometry on the resulting tape shows good agreement