3D printing of highly-loaded slurries via layered extrusion forming: Parameters optimization and control

The optimization of slurry compositions and processing parameters has significant potential for layered extrusion forming, a novel slurry-based additive manufacturing method. The optimal slurry composition was composed of 50vol.% Al2O3 loading, 1.5wt.% acetic acid as dispersant and 2wt.% methylcellulose solution as binder. The processing parameters including layer height, print speed and nozzle diameter significantly influenced the fabrication quality. The orthogonal experiment showed that the print speed of 15mm/s, nozzle diameter of 0.40mm and layer height set as 70% of nozzle diameter was the optimized processing conditions. The lattice structure constructed under the optimized conditions exhibited uniform and well-shaped morphology before and after sintering. The solid-infilled ceramic specimen prepared via optimized parameters exhibited uniform structure and the surface roughness was 0.75 mu m, which greatly improved the surface quality.