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TESTING | CHARACTERIZATION
low-amplitude waves, next steps
include exploring high-amplitude, non-
linear regimes in 3D crystals. Ultimately,
the team hopes to develop new materi-
als. For instance, granular substances
are dynamically responsive—when you
hit them harder, they react differently.
“If you could design a coating
that has unique impact-absorbing
capabilities, it could have applications
ranging from spacecraft micro-meteor-
ite shielding to improved bulletproof
vests,” notes Nicholas Boechler, assis-
tant professor of mechanical engineer-
ing.
washington.edu.
CLOSE-UP OF COPPER
CORROSION PROVES
EYE-OPENING
Using state-of-the-art in situ
microscopy techniques, scientists at
Binghamton University, N.Y., observed
the oxidation of copper at the atomic
level—andwere surprised bywhat they
saw. Using atomic resolution electron
microscopes, scientists demonstrated
that the oxidation of copper occurs via
layer-to-island growth of copper oxide
on flat copper surfaces, with copper
atoms evaporating from the surface.
Solid oxide, made of copper and oxy-
gen atoms thermally combining above
the original surface, is deposited back
on the surface. This contradicts the
long-held idea of a solid-solid trans-
formation and demonstrates that—
counterintuitively—if a surface can
be made more uneven, its oxidation
resistance increases.
MICROSCALE GRANULAR
DYNAMICS DESCRIBED
University of Washington mechan-
ical engineers observed and analyzed
collective interparticle vibrations in
2D microscale granular crystals. While
the dynamics of large-particle gran-
ular crystals have been studied, this
is the first time such behavior has
been described in microscale crystals,
which—the team discovered—exhibit
Thermo Fisher Scientific Inc.,
Waltham, Mass., acquired
FEI Co.,
Hillsboro, Ore., for approximately
$4.2 billion. FEI designs, manufac-
tures, and supports high-
performance electronmicroscopy
workflows that provide images and
information at various scales for both
materials science and life sciences.
The business will become part of
Thermo Fisher’s Analytical Instru-
ments Segment.
thermofisher.com.
BRIEFS
Lightweight Innovations for Tomorrow,
Detroit, a public-private partnership
committed to the development and deployment of advanced lightweight
metal manufacturing technologies, is establishing a team to identify newways
to mitigate corrosion in aluminum alloys.
The Ohio State University,
Colum-
bus, and
United Technologies Research Center,
Hartford, Conn., will lead
the project, in collaboration with
Lockheed Martin,
Bethesda, Md.,
DNV GL,
Norway, and the
University of Michigan,
Ann Arbor. The group will develop
computer models to predict aluminum alloy corrosion in components used in
airplanes and other modes of transportation.
www.lift.technology.
This laser ultrasonic setup allows the observation of microscale granular crystal
vibrations. Courtesy of Dennis Wise/University of Washington.
significantly different physical phenom-
ena. For example, the microscale parti-
cles respond more strongly to adhesive
forces, they resonate at higher frequen-
cies, and they interact with each other
in more complex patterns—including
a combination of horizontal expansion
and contraction, rotation, and wave
motion.
To conduct their research, the
team manufactured a 2D, ordered layer
of micron-size glass spheres through
self-assembly, then used laser ultra-
sonic techniques to induce vibration
and observe the dynamics between
particles. While the researchers used