Momentum - The Magazine for Virginia Tech Mechanical Engineering Vol. 3 No. 3 Fall 2018 | Page 26

Researchers
develop
process to 3D
print one of
Earth's
strongest
materials
Zoomed in graphene octet truss
on strawberry blossom
STORY BY ANDREW TIE
MACROMOLECULES
INNOVATION INSTITUTE
Researchers from Virginia Tech and Law-
rence Livermore National Laboratory have
developed a novel way to 3D print complex
objects of one of the highest-performing
materials used in the battery and aerospace
industries.
Previously, researchers could only pr int this
material, known as graphene, in 2D sheets or
basic structures. But Virginia Tech engineers
have now collaborated on a project that
allows them to 3D print graphene objects at a
resolution an order of magnitude greater than
ever before printed, which unlocks the ability
to theoretically create any size or shape of
graphene.
Because of its strength - graphene is one of
the strongest materials ever tested on Earth
- and its high thermal and electricity conduc-
tivity, 3D printed graphene objects would be
highly coveted in certain industries, including
batteries, aerospace, separation, heat manage-
ment, sensors, and catalysis.
Graphene is a single layer of carbon atoms
MOMENTUM
FALL 2018
organized in a hexagonal lattice. When
graphene sheets are neatly stacked on top of
each other and formed into a three-dimen-
sional shape, it becomes graphite, commonly
known as the “lead” in pencils.
Because graphite is simply packed-together
graphene, it has fairly poor mechanical prop-
erties. But if the graphene sheets are separated
with air-filled pores, the three-dimensional
structure can maintain its properties. This
porous graphene structure is called a graphene
aerogel.
“Now a designer can design three-dimen-
sional topology comprised of interconnected
graphene sheets,” said Xiaoyu “Rayne” Zheng,
assistant professor with the Department of
Mechanical Engineering in the College of
Engineering and director of the Advanced
Manufacturing and Metamaterials Lab. “This
new design and manufacturing freedom will
lead to optimization of strength, conductivity,
mass transport, strength, and weight density
that are not achievable in graphene aerogels.”
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