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Simulations based on the discrete element method (DEM) are used to investigate the relationship between the distribution of particle sizes and the macroscopic sintering behavior of ceramic powders. This is achieved by generalizing the DEM force laws for solid‐state sintering in such a way that sintering of particles with different sizes can be simulated. A generation scheme for initial particle packings with realistic physical properties is presented, which allows for different distributions, ranging from monomodal to normal, log‐normal, and bimodal distributions. It is shown that the type and width of the distribution has a significant effect on the strain rates and viscosity during sintering. Broader size distributions lead to reduced sintering rates, although particle rearrangement is enhanced. However, the accelerating effect of rearrangement is overcompensated by an increase of the contact area between particles when the size distribution becomes wider. The simulation results are in good agreement with experimental results on a commercial Al2O3 power.

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.

Particle‐based simulations using the discrete element method are applied for the sintering of thin ceramic stripes that are constrained by a rigid substrate. The inhibition of lateral particle movement in vicinity of the substrate leads to a preferred shrinkage direction perpendicular to the substrate, which causes shape distortion as well as delamination of the stripe at the interface edges. Multiple processing parameters are varied in simulations to analyze their influence on the mentioned effects. The amount of particle rearrangement and the height to width aspect ratio of the cross‐section are identified to be factors that determine the level of shape distortion and edge delamination. The simulation results are compared with measurements of stripes produced by soft micromolding in capillaries. Good accordance is observed regarding parameters like axial and lateral shrinkage or delamination angle.