EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

Embedded 3D printing is an emerging technique that allows the fabrication of complex structures inside a soft self-healing matrix and has been applied on polymers and organics. Multi-material composites with targeted structures can be obtained in a single embedded 3D printing step. Here we introduce the application of this technique to the printing of complex structures inside ceramic matrices. Both the ink and the ceramic matrix are based on thermal reversible hydrogels and inorganic powders. The approach is applicable to a wide range of material combinations and we will show here examples of ceramic/ceramic and ceramic/metal composites. In this presentation, suitable compositions and printing conditions to combine matrix healing with the stability of the internal printed structures are discussed. XCT is used to observe these internal structures and defects of the composites. We will also discuss effective strategies to engineer the interface between the matrix and the printed structure. The mechanical properties of composites with single filament, woodpile and auxetic structures are compared based on in situ and ex situ mechanical testing. The goal is to establish the rheology required to enable printing inside inorganic materials and guidelines to design composites with improved structural performance.