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A D V A N C E D
M A T E R I A L S
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P R O C E S S E S |
A P R I L
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BIOPRINTING SPURS
CARTILAGE CREATION
Using 3D bioprinting, researchers
at Chalmers University of Technolo-
gy and Sahlgrenska Academy, both in
Sweden, successfully facilitated growth
of human cartilage cells in an animal
model. “This is the first time anyone has
printed human-derived cartilage cells,
implanted them in an animal model,
and induced them to grow,” says Paul
Gatenholm, professor of biopolymer
technology at Chalmers. First, research-
ers printed a hydrogel of nanocellulose
mixed with human-derived cartilage
cells. Immediately after printing, the
construct was implanted in mice. The
team reports three positive results of
the animal study: Human cartilage tis-
sue grew in the animal model; blood
vessels formed between the materi-
als (vascularization); and neocartilage
formed and multiplied via the human
stem cells.
NEW COPPER-BASE ALLOY IS
VERY ATTRACTIVE
A team fromMaterion Corp., Cleve-
land, recently discovered a copper-base
alloy system that exhibits magnetic be-
havior. The alloy—a quaternary mixture
of copper with nickel, tin, and man-
ganese—holds promise for applica-
tions requiring magnetic performance
along with conductivity and forma-
bility. Copper alloys are characteristi-
cally nonmagnetic and transparent to
Are you working with or have you
discovered a material or its properties
that exhibit OMG - Outrageous
Materials Goodness?
Send your submissions to
Frances Richards at
frances.richard
OMG!
OUTRAGEOUS MATERIALS GOODNESS
The brown recluse’s spinning technique
could inspire tougher materials and
textiles.
In a newly discovered copper-base alloy
system, the precipitation reaction is key
to tailoring strength andmagnetics.
Ni, Mn, and Sn produces precipitates
during heat treatment, which allows
the alloy to be magnetically switched
on or off while modulating strength and
ductility. For more information: Michael
Gedeon, .
SPINNING A STURDIER WEB
New research shows that brown
recluse spiders use a unique mi-
cro-looping technique to make their
threads stronger than that of any other
spider. The study was produced by sci-
entists from the University of Oxford,
UK, and the College of William & Mary,
Williamsburg, Va. From observing the
arachnid, the team discovered that un-
like other spiders, who produce round
ribbons of thread, recluse silk is thin
and flat. This structural difference is
key to the thread’s strength, provid-
ing the flexibility needed to prevent
premature breakage and withstand
the knots created during spinning that
give each strand additional strength.
The ribbon shape adds the flexibility
needed to prevent premature failure, so
that all the micro-loops give additional
strength to the strand. By using com-
puter simulations to apply this tech-
nique to synthetic fibers, the team was
able to test and prove that adding even
a single loop significantly enhances ma-
terial strength. wm.edu.
Image: Spider pic
magnetic fields, and also exhibit very
low permeability, particularly when
iron impurities are absent. This mag-
netic transparency favors use in elec-
trical systems and magnetic sensing
equipment such as directional drilling
sensors for oil and gas. In contrast, the
new alloy system shows potent age
hardenability with the ability to mod-
ify magnetic properties by controlling
the age hardening reaction. The alloy
family includes strength combinations
up to 1170 MPa (170 ksi) and a variety
of magnetic hysteresis loop behaviors
describing magnetic moment at satura-
tion up to 1.4 emu and tailorable levels
of remanence, coercivity, and perme-
ability. Controlled supersaturation of
Illustration shows formation of blood vessels in the bioprintedmaterial implanted in
an animal model. Courtesy of Philip Krantz.