Loading Events
All Events
  • This event has passed.

Seminar – Optical 3D printing processes for lightweight, scalable 3D metamaterials – Dr. Xiaoyu Zheng

September 16, 2016 @ 11:30 am

Event Navigation

Dr. Xiaoyu Zheng

Assistant Professor, Department of Mechanical Engineerin, Virginia Tech

 

Optical 3D printing processes for lightweight, scalable 3D metamaterials

 

It has been a long research and engineering pursuit to create lightweight and

mechanically robust and energy efficient materials with interconnected porosity.

These cellular materials are desirable for a broad range of applications including

structural components, lightweight transportation, heat exchange, catalyst

supports, battery electrodes and biomaterials. However, the required outstanding

properties have remained elusive on lightweight materials (<10kg/m3),

constrained by the inherent coupling of material properties and the lack of

suitable processes to generate these artificial materials. For example, graphene

aerogels have among the lowest record densities ~1kg/m3, but their strength

have been degraded to tens to hundreds of Pascal (<10^-8 of that of carbon

nanotubes). The attainment of low density has come with a price — – significant

reduction of bulk scale properties. In this talk, I will first overview Virginia Tech’s

research’s trusts on advanced manufacturing capabilities and novel materials by

design. I will then focus on our recent efforts on design and manufacturing of

lightweight materials with controlled three-dimensional architectures from the

macroscale to nanoscales using a suite of unique optical additive manufacturing

approaches. These 3D bulk metamaterials (polymer, metal, ceramic and

combinations thereof) possess weight density comparable to that of carbon

aerogel, but with over 10^5 higher stiffness and strength. By designing and

studying their hierarchical architectures, material compositions and feature sizes

spanning multiple length-scales, we create a wide range of low density materials

with programmable properties including tunable stiffness and strength, high

fracture tolerance as well as addressable deformation capabilities. With the

possibility of incorporating precise control of topological architectures across

unprecedented disparate length-scale sets, we enter into a paradigm where

nanoscale material properties can be harnessed and made accessible in large

scale objects, opening a wide range of applications of these materials in energy,

health care and flexible electronics.

 

Xiaoyu (Rayne) Zheng is an Assistant Professor of Mechanical Engineering and

directs the Advanced Manufacturing and Metamaterials Laboratory at Virginia

Tech. He also holds an affiliate position at the Macromolecules and Innovation

Institute at Virginia Tech. Prior to joining Virginia Tech in September 2015, he

had been a Principle Investigator and Member of Technical Staff with the

Materials Engineering Division, DOE Lawrence Livermore National Laboratory,

Livermore, California since 2011. He received his Ph.D. degree in Mechanical

Engineering from Boston University in 2011 with the Best Dissertation Award.

From 2011 to 2015, worked at a member of technical staff at Lawrence

Livermore National Laboratory developing low density hierarchical metamaterials

and advanced additive manufacturing processes capable of three-dimensional

features at the micro- and nano-meter scale with a range of materials from

polymer, metal, ceramic to composites. The key focus of Zheng’s research at

Virginia Tech is to combine a suite of novel additive manufacturing (3D printing)

technologies and design tools to enable the design, analysis, and fabrication of

multi-scale, three-dimensional materials and systems that possess extraordinary

and unique capabilities for lightweight structural, energy and biological

applications. He has published over 40 journal articles, proceeding papers and

book chapters including Science and Nature Materials where his most recent

research on 3D micro-architected materials were both featured on the front

pages. Zheng received Best Paper Award at 2010 IEEE Sensor Conference,

Best Poster Award at Materials Research Society and the President Award at

Boston University and Directorate Publication Excellence Award at Lawrence

Livermore National Laboratory in 2013 and 2015. His work has been widely

reported by R&D Magazine, Science Daily, MIT front page, MIT Technology

Review, Materials Today, Nano Today, Material Research Society Bulletin,

American Physics Society etc.

Details

Date:
September 16, 2016
Time:
11:30 am
Event Categories:
,

Venue

EB3 2201