Additive Manufacturing as a Unique Platform for Fabrication of (Meta-)Materials with Complex Topologies and Designer Microstructures

Abstract 

Additive Manufacturing (AM) allows rapid fabrication of geometrically complex parts without expensive tooling. Nanoscale AM techniques, such as two-photon polymerization Direct Laser Writing, have demonstrated enormous success in fabricating a wide range of nano-architected materials, where the local scale of the architecture is so small that size effects on materials properties yield materials with unprecedented performance. Examples of truss-based, shell-based and plate-based nano-architected materials will be discussed. Importantly, though, the ability to control properties with micro/nano-scale resolution is not limited to nanoscale AM processes, as even large-scale techniques such as Laser Powder Bed Fusion (LPBF) and Cold Spray (CS) fabricate parts via addition of microscale building blocks. The ability to control the evolution of these blocks during printing opens opportunities for fabrication of both architected and bulk large-scale AM materials with accurately tailored micro/nano-structural features. We present metal/metal composites and shell-based architected materials produced by LPBF of steel with locally tailorable microstructure.

Bio

Prof. Valdevit received his MS degree (Laurea) in Materials Engineering from the University of Trieste, Italy (in 2000) and his PhD degree in Mechanical and Aerospace Engineering from Princeton University (in 2005). He worked as an intern at the IBM T.J. Watson Research Center and as a post-doctoral scholar at the University of California, Santa Barbara. He joined the faculty in the Mechanical and Aerospace Engineering Department at the University of California, Irvine in 2007. In 2018, he moved his appointment to the newly established Department of Materials Science and Engineering, where is currently professor and chair. He is a Fellow of the American Society of Mechanical Engineers (ASME), the recipient of the 2007 Faculty Award from IBM Corporation, the 2012 Popular Mechanics Breakthrough Award and the 2018 Outstanding Faculty Service award from the School of Engineering at UCI. Prof. Valdevit works in the general areas of mechanics of materials, structural materials science and advanced manufacturing, developing analytical, numerical and experimental techniques across multiple length scales. Among his primary research goals are the optimal design, modeling, fabrication and experimental characterization of metamaterials and structures with unprecedented combinations of properties. Current areas of interest are the investigation and exploitation of beneficial size effects in nano-architected materials, the non-linear design of periodic and disordered mechanical metamaterials, and the understanding of the processing / microstructure / properties relations in additive manufacturing (in particular, two-photon polymerization Direct Laser Writing, Direct Ink Writing, Laser Powder Bed Fusion and Cold Spray Deposition). 

All seminars are held on Wednesdays from 12:00 -1:00 p.m. in the Bowen Hall Auditorium Room 222. A light lunch is provided at 11:30 a.m. in the Bowen Hall Atrium immediately prior to the seminar.