Simulation and experimental analysis on the deformation rate on slender rod parts during the recoating process in high viscosity ceramic stereolithography

In the recoating process of the high-viscosity ceramic stereolithography, a large amount of ceramic paste is accumulated in front of the blade, and the fluidity of the high-viscosity ceramic paste is poor. The blade imposes forces on the solid part below, which deforms the fine structures of the part, affecting the accuracy of the part. In the actual printing process, slender rod parts appear T-shaped. This paper aims to investigate the causes of this phenomenon and to predict the deformation rate of a part. The understanding of the deformation phenomena can be used as theoretical guidance for dimensions or support sizes when modeling parts. A two-dimensional model has been developed to study high-viscosity materials with non-Newtonian fluid properties and slender rod parts, using the phase field method and a dynamic mesh to restore the recoating process. An experimental setup, which mimics the recoating process in the high-viscosity ceramic stereolithography process, has been used to verify the results of simulations. The results show the force exerted by the blade only affects the top portion of the slender rod part, and that the time of greatest impact on the deformation is the moment when the blade is reaching the top of the slender rod, generating a deformation rate that is cubic to the height of the slender rod.