PurposeThe purpose of this paper is to present a new ceramic suspension to fabricate complex ceramic parts by stereolithography (SL).Design/methodology/approachThe process consists of preparation of aqueous ceramic suspensions, building ceramic parts, drying, subsequent binder removal, and sintering. Highly concentrated aqueous ceramic suspensions with a suitable viscosity are prepared, then a wet green ceramic part fabricated in a SL machine according to a 3D model is dried in polyethylene glycol. After binder removal sintering in a high temperature‐sintering furnace, a complex ceramic part is obtained.FindingsThe dispersant, volume fraction of ceramic powder and powder diameter could influence the viscosity of suspension. The cured depth is inversely proportional to the scanning speed of laser spot when the laser power keeps a constant and proportional to the concentration of monomer. The penetration depth and critical exposure are 0.27 mm and 231.2 mJ/cm2 from the experimental result of the windowpanes method. A new support structure could prevent the deformation of ceramic part from the suspension and improve the quality of ceramic parts. A complex impeller is fabricated at last.Research limitations/implicationsThe dimensional and surface accuracy of ceramic SL should be further investigated.Originality/valueThis paper describes a new aqueous ceramic suspension to produce complex‐shaped ceramic parts by SL.

The purpose of this paper is to develop the relationships between ceramic stereolithography (SL) process parameters and curing characteristics of a ceramic suspension. A recently developed photocurable aqueous-based silica suspension with high solid loading (50 vol%) was employed to run small batch experiments. Basic structural building units including single line and layer parts were fabricated, based on a new building scheme to establish the predictive equations with the ceramic SL process parameters. The curing profiles of this silica suspension were also observed and analysed. The photosensitive parameters were determined. Some comparisons were made with conventional resin. The influence of the scattering effect was discussed. With the adequate process parameters chosen, the cured layers could achieve a sufficient depth (higher than 200 μm) and the ceramic green parts obtained could possess appropriate adhesions between adjacent cured lines and layers. Finally, using these parameters, several of the structural and functional ceramic components were built and demonstrated; the dimensional resolution reached was about 0.1 mm.

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In this work, the influences of stereolithography parameters (laser scanning speed, sliced layer thickness, laser spot compensation, etc.) and sintering schemes, consisting of sintering temperature, heating rate and holding time on the performance of green and final ceramic parts, have been investigated experimentally with the Taguchi method. In the stereolithography process, laser spot compensation was found to be the principal factor influencing the shrinkage of green samples. Optimum stereolithography parameters were obtained: hatch spacing 0.15 mm; laser scanning speed 1400 mm/s; sliced layer thickness 0.15 mm; and laser spot compensation 0.35 mm. A freeze-drying method was applied to minimize the drying shrinkage and avoid damages during the dehydration process of green samples. The optimum sintering scheme was also determined: heating rate 150°C/h, sintering temperature 1200°C and holding time 2 h. A bending strength of at least 10 MPa and open porosity of 35% were reached, making the ceramics adequate to produce investment casting molds.

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