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A D V A N C E D M A T E R I A L S & P R O C E S S E S | M A R C H 2 0 1 5
8 METALS | POLYMERS | CERAMICS
MASSACHUSETTS
INSTITUTE OF TECHNOLOGY,
CAMBRIDGE, RESEARCHERS
FIGURED OUT EXACTLY WHICH
CHARACTERISTICS OF A
METAL STRUCTURE TEND TO
FOSTER EMBRITTLEMENT IN
OIL WELL TUBES LINED WITH
METAL IN THE PRESENCE
OF HYDROGEN. THEY ALSO
DETERMINED THAT SIMPLE
CHANGES IN PROCESSING
CAN MODIFY THE STRUCTURE
IN A WAY THAT MAY GREATLY
REDUCE THE CHANCES OF
DAMAGE, EXTENDING THE
SAFE OPERATING LIFETIME.
BRIEFS
Blueshift International Materials Inc. , San Antonio, introduced a commercially
available polyimide aerogel, which combines the physical and toughness properties
of plastic films with the insulation properties of aerogels to create a strong yet light-
weight, thin, clean, and flexible insulator. The product’s 100% polyimide polymer
construction eliminates dusting as well as dangerous handling protocols.
.
ELECTROCHROMIC POLYMERS
CREATE A RAINBOW OF COLOR
Researchers created a broad color
palette of electrochromic polymers, ma-
terials that can be used for sunglasses,
window tinting, and other applications
that rely on electrical current to produce
color changes. Supported by BASF, Ger-
many, the research was conducted in the
laboratory of John Reynolds, a professor
at the Georgia Institute of Technology,
Atlanta. “We’ve demonstrated the abil-
ity to create virtually any color we want
by mixing different electrochromic poly-
mers, just like mixing paint,” says Reyn-
olds. “Using a simple coating method or
even inkjet printing, we can create films
that change color with the application of
a voltage.”
The electrochromic materials rely
on a reduction-oxidation reaction trig-
gered by the application of an electri-
cal potential provided by a simple coin
battery—a positive one volt causes the
glasses to be clear, while a minus one
volt switches to the color. “Essentially,
we are just charging and discharging
the device, which is what causes the col-
or change,” Reynolds explains. For more
information: John Reynolds,
,
UNCOVERING OXYGEN’S
EFFECT ON TITANIUM
University of California, Berke-
ley, scientists found the mechanism by
which titanium becomes brittle with just
a few extra atoms of oxygen. This discov-
ery has the potential to open the door to
more practical, cost-effective use of tita-
nium in a broader range of applications.
Andrew Minor, associate professor
of materials science and engineering,
led a research team focused on solving
the long-standing metallurgical mystery
of how oxygen causes such a profound
change in the characteristics of metals.
Researchers subjected various grades of
titanium samples to nanocompression
A cross-section of grade 3 titanium
(containing 0.3% oxygen) placed under
stress and deformed. Defects are evident.
Oxygen impurities force the defects to
spread onto different planes of the
material. Courtesy of Qian Yu.
Samples of some colors produced in electrochromic polymers. The materials can be
used for applications such as sunglasses and window tinting that can be turned on
and off through the application of an electrical potential. Courtesy of Rob Felt.