3D printed dielectric ceramic without a sintering stage.

Traditional ceramic fabrication requires sintering, a high-temperature process that can introduce defects and limit design flexibility. Prior research has shown that sintering is essential for achieving high-density ceramics. That uncertainty drove exploration of alternative methods. This gap motivated investigation into 3D printing as a sintering-free alternative. No prior work had resolved how to achieve ceramic densification without heat treatment. It was already known that material extrusion could produce complex geometries. However, the role of solvents and dissolution in ceramic consolidation remained unclear. This paper's contribution is a novel approach to ceramic fabrication that bypasses sintering entirely.

The aim was to develop a 3D printing method for dielectric ceramics that eliminates the need for sintering. The specific problem addressed is the reliance on high-temperature processing in ceramic manufacturing. This approach could reduce energy use and expand design possibilities. The motivation stems from limitations in conventional sintering-based methods. The researchers propose using dissolution and recrystallization during printing. This method could be applied to other ceramic materials and composites. The goal was to achieve high density and dielectric performance without sintering. The study tests whether extrusion pressure and capillary forces alone can consolidate ceramic parts.

The printable paste was made by mixing Li2MoO4 powder with water. The solid content was adjusted to 60.0 vol.%. A syringe-style 3D printer was used for material extrusion. The paste was extruded layer by layer to form disc-shaped samples. Consolidation occurred during printing due to extrusion pressure. Capillary forces and recrystallization of dissolved Li2MoO4 aided densification. The printed parts were dried at 120 °C to remove residual water. Microstructural analysis confirmed no delamination between printed layers.

The printed discs achieved high density without sintering. Dielectric properties were comparable to conventionally sintered ceramics. The microstructure showed no layer delamination after printing. Densification occurred through extrusion and capillary forces. The drying step at 120 °C ensured complete solvent removal. Recrystallization of Li2MoO4 contributed to structural integrity. The method produced parts with smooth surfaces and consistent dimensions. These results suggest the approach is viable for other ceramic materials.

The authors propose that sintering can be eliminated in ceramic fabrication. The method relies on dissolution and recrystallization during printing. No high-temperature processing was required for consolidation. The results suggest this approach is applicable to other ceramic systems. The printed parts achieved high density and good dielectric performance. The method is compatible with low-cost 3D printing equipment. This study demonstrates a feasible alternative to traditional sintering. The findings indicate potential for broader application in ceramic manufacturing.