Speaker: Xiaoyu Rayne Zheng, Assistant Professor

Affiliation: Department of Mechanical Engineering, Virginia Tech

Achieving More with Less: Additive Manufacturing and Multiscale 3D Architected Metamaterials

Material properties are constrained by their chemical composition and spatial arrangement of their constituents at multiple length scales. This limits material properties with respect to each other creating trade-offs when selecting materials for specific applications. For example, few solid materials exist considerably lighter than water. To decrease the density beyond this point, materials must have a porosity, which comes at the cost of a disproportional degradation of other desirable properties.

I will present our research on designing additive manufacturing and performances of new classes of multi-functional materials that transcend these coupling limitations: 3D architected metamaterials. These materials are as light as carbon aerogels, but with orders of magnitude higher stiffness, strength and possess multi-functionalities. They are comprised of interconnected 3D hierarchical micro-structures as designed “atoms” and “molecules” as in natural materials to reach uncharted white space in the material selection charts. Attention is focused on our development of a suite of novel additive manufacturing and processing techniques to synthesis traditionally unprocessable inorganic/organic building blocks and architect them into scalable form factors with precisely defined 3D micro- and nano-scale features. Through designing, optimization and characterization of their unique property-structure-process relationships, we introduce designed-in attributes from disparate physical property space into these metamaterials. These attributes include lightweight, flexibility, fracture and high temperature resistant, sensing and actuation, which could transform our ability to tailor new properties and functionalities out of a single material block with only a fraction of solid, as opposed to relying on multiple components.

About the Speaker

Dr. Xiaoyu Rayne Zheng is an Assistant Professor of Mechanical Engineering at Virginia Tech and directs the Advanced Manufacturing and Metamaterials Laboratory. His group draws from the principles of mechanics, optics and materials science to develop the next generation of additive manufacturing techniques and processes capable of arbitrary, hierarchical 3D architected materials for multi-functional applications. Prior to joining Virginia Tech, from 2011 to 2015, he was a Member of Technical Staff at DOE Lawrence Livermore National Laboratory (LLNL) in the San Francisco Bay Area, where he worked on high volume of additive manufacturing initiatives and materials with controlled micro-architectures (DARPA MCMA). His prior work on architected metamaterials was selected as one of the Top 10 Innovations from MIT Technology Review. His current group has been funded by NSF, ONR, AFOSR and DOE. He received his Ph.D. degree in Mechanical Engineering from Boston University in 2011 with the Outstanding Dissertation Award. Zheng has published over 40 journal articles, proceeding papers and book chapters, including cover articles on Science and Nature Materials. He received the Air Force Young Investigator Award, Inventor’s Award from Virginia Tech, ICTAS Junior Faculty Award, LDRD Award and Director’s Award for Publication Excellence from LLNL.