A vat photopolymerization–assisted multi-material printing method: Enabling good interface bonding and multi-function structure design

Multi-material structures have been widely used in aerospace, medical, food engineering and other fields owing to their excellent mechanical properties. However, the fabrication of intricate multi-material structural components through three-dimensional (3D) printing technology presents a challenging task. While some 3D printing technologies are capable of fabricating multi-material structures, issues related to insufficient precision and low efficiency often arise. In this work, a novel multi-material vat photopolymerization 3D printing technique is proposed. The proposed printing technology integrates digital light processing curing technology with a multi-material delivery system to facilitate the efficient and high-quality 3D fabrication of complex structures using multiple materials. Therefore, it can not only facilitate the production of complex multi-material structures but also preserve the high resolution and printing efficiency. Using the proposed 3D printing system, the mechanical properties of the multi-material specimens were examined, and a strong correlation was found between the interface bonding strength and the printing orientation. Finally, the efficiency and application potential of this printing technique was illustrated through some exploratory product applications in energy absorption, electromagnetic shielding, and flexible sensing.