Lightweight mechanical metamaterials towards their theoretical limits of stiffness and strength: a design and additive manufacturing study


Mechanical metamaterials are a class of architectured materials which possess exceptional and tailorable mechanical and physical properties by engineering their internal lattice structures. The lightweight and multifunctional properties of metamaterials make them widely used in diverse applications, such as aerospace and biomedical engineering. However, manufacturing these geometrically complex structures has been a challenging task. The rapid development of additive manufacturing (AM) technology in this decade makes them possible. To fully explore the achievable mechanical properties of metamaterials, two research tasks should be performed systematically: (1) identification of lattice structures with optimal mechanical properties and (2) minimization of defects induced by AM processes. In this talk, our latest research progress on the development of truss- and shell-based lattice structures with superior stiffness and strength via analytical, numerical, and experimental methods will be presented. The geometric defects of selective laser melting fabricated structures, the influence of defects on mechanical properties, and compensation methods will be discussed. Finally, the applications of our proposed metamaterials in the fields of lightweight structural components, bone scaffolds, and electrode structures will be demonstrated, which completes the whole journey of metamaterial and structural development from design, manufacturing, and characterization towards applications.

講者/ 表演者:


Dr. ZHANG Lei is a postdoc fellow at the Department of Mechanical and Aerospace Engineering, the Hong Kong University of Science and Technology. He received his Ph.D. degree in Mechanical Engineering from National University of Singapore in 2019, and bachelor's degree in Precision Machinery and Precision Instrumentation from University of Science and Technology of China in 2014. He worked as a research scientist in Singapore Institute of Manufacturing Technology from 2019 to 2020. Dr. Zhang’s research interests are analytical, numerical design optimization methods for mechanical metamaterials, additive manufacturing (AM) technologies, and geometric defect analysis for AM fabricated structures. He has many publications in structural design and additive manufacturing, amongst which two are listed as top cited articles in prestigious journals “Additive Manufacturing” and “Materials and Design” with citations more than 150 times in less than 3 years duration. His primary research goals are the optimal design, accurate numerical prediction, high-quality AM fabrication of metamaterials and structures for lightweight structural and functional applications.

Systems Hub, HKUST(GZ)