Direct Ink Writing (DIW) is an additive manufacturing technique that is based on printing three-dimensional objects by deposition of ink by lines and layer by layer by extrusion. In ceramic printing, ceramic suspensions obtained from powdered particles are one of the most widely used methods. However, this ceramic powder requires the use of compounds that prevent its agglomeration and/or sedimentation, improve the homogeneity and stability of the suspension, reduce its viscosity, or improve its workability. There is an alternative route to the use of ceramic powder in the preparation of printing inks that are based on the use of ceramic precursors.
In this work, to obtain alumina ceramic pieces instead of using alumina suspensions, the use of ceramic precursors based on inorganic salts of aluminium soluble in water has been studied. The inks have been developed by optimizing rheology and proportion between salt and gelling agent. Drying, debinding, and sintering process conditions are studied by thermogravimetric analysis. The final microstructure has been evaluated by scanning electron microscopy and its crystalline phases by X-ray diffraction.