Additively manufactured composite lattices: A state-of-the-art review on fabrications, architectures, constituent materials, mechanical properties, and future directions

Finding ideal materials remains a crucial challenge in the aerospace, automotive, construction, and biomedical industries. Moreover, a growing concern about environmental burden and fuel consumption has triggered strong demand for lightweight materials with high-performance multifunctional characteristics. Composite lattices exploiting topological and constituent materials are of particular interest thanks to their excellent mechanical properties and lightweight that can ideally meet critical design requirements. However, composite lattices are integrated with high complexity in their geometries, which creates challenges in their manufacturing in practice. Additive manufacturing (AM) technologies have been extensively developing to provide more freedom in manufacturing to support the growing interest in fabricating these innovative materials with intricate geometry. This paper reviews current studies on additively manufactured composite lattices. First, AM and post-treatment techniques and their capability for fabricating complex structural materials are discussed. Then, several types of structural configurations and characteristics of AM composite lattices are reviewed. Further, the mechanical properties of these composite lattices are analyzed and the role of reinforcing phases is discussed in detail. Finally, the review highlights some potential future research directions and opportunities of 3D printed composite lattices for energy absorption, recoverability, specific strength and stiffness, and weight lightening.