Magnetics Business & Technology - Summer 2015 - (Page 22)
RESEARCH & DEVELOPMENT
MagLab Claims Record with Novel Superconducting Magnet
A MagLab-made magnet that is more of
LTS cousins, a big plus. That property also
a strong, silent type nonetheless made a
allows them to remain superconducting to
loud splash when it broke the world record
much higher magnetic fields than LTS mafor an all-superconducting magnet.
Built with both traditional and novel
The magnet tested in June features a
superconducting materials, the magnet
mix of YBCO tape and LTS wire, as will the
reached a field of 27 teslas on June 5 in a
finished 32 T. SuperPower president Yusei
test that exceeded designers' expectations.
Shirasaka shared the excitement over the
The magnet is a smaller version of an even
achievement and his company's partnermore powerful magnet due for completion
ship with the MagLab.
"Our relationship with the MagLab has
next year, a 32 tesla all-superconducting
allowed us to grow and learn, with the
magnet that will be substantially stronger
constant drive to perfect our products,"
than any such magnet built to date.
Shirasaka said. "SuperPower's recent ad Tesla (T for short) is a measure of magvances in pinning structure, thinner subnetic field strength: A typical magnet used
strates and other improvements will form
in an MRI machine is 2 to 3 T. The 27 T field
the basis for the MagLab's next generareached last week was 3.5 T stronger than
tion of magnets."
the strongest superconducting magnet currently in operation (in Lyon, France) and
Another partner on the 32 T project was
1 T stronger than a superconducting test
Oxford Instruments, which constructed the
magnet built earlier this year in South KoLTS coils. The HTS coils and other key techrea. For decades, engineering and materials
nologies were developed and constructed
advances have nudged the record up only
at the MagLab. The prototype that intebit by bit. Last week's feat brings MagLab
grates the LTS and HTS coils performed
engineers to the home stretch of the sevenbeautifully in its tests, reported MagLab
year 32 T project.
engineer Huub Weijers. As director of the
32 T project, Weijers has tested a number
"It's been a very difficult and long road,
to such an extent that some people have This YBCO test coil helped the MagLab set a of magnet coils over the years.
"This is the first time with the prowondered whether these magnets would new world record for superconducting magtotypes that we've not had something
ever become a reality," said MagLab Direc- nets: 27 teslas.
that wasn't quite right," Weijers said of
tor Greg Boebinger. "So to make such a
last week's test. "Every time, there was
huge stride with this next-to-final version
a piece here or a part there that wasn't
of the magnet gives us great optimism that
quite right, that was limiting us overall.
the completed 32 T magnet will perform
This time there was no such irregularity.
to spec, representing the biggest breakthrough in superconducting magnet techWe just reached the maximum perfornologies, in terms of peak fields, since the
mance of the conductor, which is ideally
where you'd like to get."
As the name suggests, superconducting
The MagLab boasts several instruments
magnets are made with superconductthat are stronger than 32 T, including two
ing materials, materials that carry current
resistive magnets and the world-record
without the friction (and attendant heat)
45 T hybrid magnet. However, as the
found in regular electricity. The catch with
world's strongest superconducting, the
conventional low-temperature supercon- The high-temperature superconductor ytrium 32 T will be able to run longer hours, be
ductors (LTS) is that they operate only at barium copper oxide -- YBCO for short -- was cheaper to operate, and offer important
painstakingly fashioned into a tape, then wound
exceedingly cold temperatures, around to make the magnet's insert coils.
advantages for some types of experi-460°F. For the past three decades, almost
ments. Superconductors create steadier,
all superconducting magnets have been
"quieter" fields than resistive magnets
made with niobium tin and niobium titanium wire, both LTS materi- (which depend on conventional current) that are important for
als that need liquid helium to stay cold. But limits inherent to those experiments in nuclear magnetic resonance, electron magnetic
materials have prevented engineers from making more powerful resonance and other areas of research that require more sensisuperconducting magnets.
Enter YBCO, a superconducting material discovered in 1986 that, The successful test gives Weijers and his team new momentum
after years of development, is expected to make its debut as a as they approach the final phases of the project. The completed
magnet for scientists in the finished 32 tesla. Short for yttrium 32 T magnet is projected to be ready for scientists in the first half
barium copper oxide, YBCO is a high-temperature superconductor of 2016.
(HTS) that was fashioned into a tape-like form by SuperPower Inc. "We pushed it to the limit," said Weijers. "All those things comof Schenectady, NY, in collaboration with the MagLab. HTS super- bined make us quite confident that we can make 32 T."
conductors are superconducting at higher temperatures than their "Knock on wood," added Boebinger.
Magnetics Business & Technology * Summer 2015
Table of Contents for the Digital Edition of Magnetics Business & Technology - Summer 2015
Bonded Magnets: A Versitile Class of Permanent Magnets
Spintronics on Paper: The Whys and Wherefores
Magnets, Materials & Assemblies
Software & Design
Research & Development
Marketplace / Advertising Index
Spontaneous Thoughts: The Rate Determining Step
Magnetics Business & Technology - Summer 2015