This publication presents a solid freeform fabrication technique for ceramics in the alumina-silica system by layering binder-free, high-loaded ceramic slurries, followed by selective laser sintering. The low melting silica phase and the reaction sintering between silica and alumina favor the rapid prototyping of pure ceramic parts. On the basis of electroacoustic and viscosity measurements, stable slurries from Al 2 O 3 /SiO 2 powder mixtures and water with a high fluidity have been prepared for the layer deposition with a doctor blade like in tape casting. Layers with a thickness of about 100 lm were processed. It was found in laser parameter studies that ceramic parts can only be obtained using special alumina contents and laser parameters. But the biphasic approach may allow greater flexibility in the processing regime than is afforded by the use of just one material. The microstructure of these parts depends mainly on the temperature gradient induced by the laser absorption and thermal conduction. The wet shaping facilitates laser-sintered parts with a relatively high density, which could be increased by a thermal post-treatment.

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The present work presents first results obtained with a new semi‐solid freeform fabrication technique for ceramic products. It is a combination of three‐dimensional (3D) surface milling and laser surface sintering (3D‐LSS). By using the 3D‐LSS technique, complex‐shaped vitreous silica prototypes with high durability have been constructed.

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