Work

Embedded 3D printing of microstructured multi-material composites

Year: 2023

Type: article

Abstract: Additive manufacturing could open new opportunities in the design and fabrication of advanced composites and devices incorporating multiple phases. However, when it comes to the combination of inorganic materials (ceramics and metals) it is difficult to achieve the degree of structural control demanded by many advanced applications. To address this challenge, we have developed a means of embedded printing to build complex, fine structures within dense ceramics. We have formulated a self-healing ceramic gel that enables the movement of a printing nozzle in its interior and that heals without defect after it has passed. Upon subsequent heat treatment, the gel forms a dense, defect-free ceramic that encapsulates the printed structure. We demonstrate the potential of the technique through two case studies. One is the printing of light, sacrificial graphite structures to introduce complex microchannel arrangements in a ceramic for applications such a thermal management. The other is to embed dense steel framework structures in aluminum oxide to increase its fracture resistance. The approach enables the introduction of auxetic structures that generate works of fracture 50% greater than those obtained with simple fibre arrays and that are orders of magnitude above the fracture energy of the ceramic. These results suggest that embedded 3D printing can open the way to implement new designs in ceramic matrix composites.

Source: Matter

DOI: 10.1016/j.matt.2023.10.031