Transcript Slide 1
Prospects for High Temperature
Superconducting Magnets
David Larbalestier
National High Magnetic Field Laboratory, Florida State
University, Tallahassee FL 32310
NHMFL User Committee Meeting
October 2, 2009
YBCO properties: Aixia Xu, Fumitake Kametani, Jan Jaroszynski, Youri Viouchkov
YBCO coil R+D and test: Ulf Trociewitz, Huub Weijers, Patrick Noyes, Bill Shepherd, Ken
Pickard, Denis Markiewicz
Bi-2212 Coil and test: Ulf Trociewitz, David Myers, Jianyi Jiang, Eric Hellstrom, Huub
Weijers, Patrick Noyes
YBCO conductor by SuperPower (Venkat Selvamanickam, Yi-Yuan Xie, Drew Hazelton and
colleagues)
Bi-2212 conductor by Oxford Superconducting Technology (Yibing Huang, Hanping Miao
and colleagues) and processing by Jianyi Jiang, Tengming Shen, Michael LoSchiavo, Eric
Hellstrom)
Themes (November 2008)
All superconducting high field magnets
provide a technology pull for HTS conductors
The needed conductors are now here and have
been tested in small coils made at the MagLab
to B > 30T
An all superconducting user magnet has been
designed (~32 T, 34 mm 4K bore)
The January NSF Major research instrumentation
program provides a vehicle to seek funding for such
a magnet
Slide 2
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
Some words from the 2008 User
Committee report
“The prospect of an all-superconducting
32 tesla magnet is very exciting. This
could reduce operating costs while
allowing more measurements to be done,
particularly for fixed field measurements
such as NMR and specific heat, and
indeed this is an exciting development for
the field as a whole. “
Slide 3
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
January 2009 Major Research Instrumentation
(MRI) Program Submission
MRI: Development of a 32 T All-Superconducting Magnet System
using YBa2Cu3O7-x Coated Conductors
PIs: Denis Markiewicz and David Larbalestier, (National High
Magnetic Field Laboratory, Florida State University), and Stephen
Julian (Department of Physics, University of Toronto).
The Intellectual Merit of Our Goals: Our goal is an allsuperconducting 32 T magnet. The enabling technology is YBCO
(YBa2Cu3O7-x) thin-film coated high temperature superconductor
(HTS-CC) which has just become available in 0.1-1 km lengths.
YBCO CC offer the possibility of transforming superconducting
magnet technology, because its 4 K critical fields are well above
100 T, compared to the 30 T of Nb3Sn from which magnets can
only made with maximum fields of about 22 T.
Slide 4
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
32 T Magnet Parameters
Total field
32 T
YBCO
Field inner YBCO coils 17 T
Field outer LTS coils
15 T
Cold inner bore
32 mm
Uniformity
5x10-4
Current
186 A
Inductance
436 H
Stored Energy
7.54 MJ
Nb3Sn
NbTi
1cm DSV
Good news – fully funded at $2 million over 3 years starting
10/09 – talk by Denis Markiewicz on the tour
Slide 5
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
The Global Context is provided by
COHMAG- Opportunities in High
Magnetic Field Science – 2004
Grand magnet
challenges:
30T NMR (All SC)
60T Hybrid (R + SC )
100T Long Pulse (R)
All require materials in
conductor forms that were not
available in 2004
They now are!
Means:
….the involved communities [users and magnet
builders] should cooperate to establish a consortium
whose objective would be to address the fundamental
materials science and engineering problems that will
have to be solved…….. COHMAG report 2004
Slide 6
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
..and locally by user demands, the
power bill, and the NSF budget….
Provides the world’s highest magnetic fields
45T DC in hybrid, 32 mm warm bore
Purely resistive magnets: 35T in 32 mm warm bore, 31 T in 50
mm bore and 19T in 195 mm warm bore
20 MW resistive magnet ~$2400/hr at full power
Slide 7
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
HTS greatly extends the capability at 4K
10000
YBCO B Tape Plane
YBCO B|| Tape Plane
Compiled from
ASC'02 and
ICMC'03 papers
(J. Parrell OI-ST)
1000
JE (A/mm²)
SuperPower tape used in
record breaking NHMFL
insert coil 2007
RRP Nb3Sn
Nb-Ti
427 filament strand with
Ag alloy outer sheath
tested at NHMFL
2212
YBCO Insert Tape (B|| Tape Plane)
Maximal JE for
entire LHC NbTi strand
production
(CERNT. Boutboul '07)
100
MgB2
YBCO Insert Tape (B Tape Plane)
MgB2 19Fil 24% Fill (HyperTech)
Bronze
Nb3Sn
2212 OI-ST 28% Ceramic Filaments
NbTi LHC Production 38%SC (4.2 K)
Nb3Sn RRP Internal Sn (OI-ST)
4543 filament High Sn
Bronze-16wt.%Sn0.3wt%Ti (MiyazakiMT18-IEEE’04)
18+1 MgB2/Nb/Cu/Monel
Courtesy M. Tomsic, 2007
Nb3Sn High Sn Bronze Cu:Non-Cu 0.3
10
0
5
10
15
20
25
30
35
Applied Field (T)
Courtesy Peter Lee www.asc.magnet.fsu.edu
Slide 8
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
40
45
YBCO Coated conductor by SuperPower
(Guilderland NY) – available since mid 2007
45
Phenomenal Jc in
the YBCO - ~20 x 106
A/cm2 at 25T
4.2K//c
4.2K//ab
40
30
2
Jc (MA/cm )
35
YBCO is ~1% of
cross-section
50% is high
strength superalloy
25
20
15
10
5
0
0
5
15
20
0H (Tesla)
2 m Ag
1 m HTS
~ 30 nm LMO
20m Cu
~ 30 nm Homo-epi MgO
~ 10 nm IBAD MgO
< 0.1 mm
50m Hastelloy substrate
20m Cu
Slide 9
10
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
25
30
35
YBCO Test Coils – ’09 update
Slide 10
SuperPower I.
SuperPower II.
NHMFL I.
NHMFL II.
Bmax = 26.8 T
Bmax = 27 T
Bmax = 33.8 T
Bmax = 20.4 T
ΔB = 7.8 T
ΔB = 7 T
ΔB = 2.8 T
ΔB = 0.4 T
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
Bi-2212 round wire technology too
– layer winding, cablable conductor
Bi2212 Ag-sheathed conductor
before heat treatment
Bi-2212 filaments after heat treatment
Round wires enable
cabling into the high
current conductors
needed for large magnets
or fast ramp magnets
Arno Godeke Magnet Group, LBNL
Slide 11
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
HTS insert coil trends – ’09 update
year
BA+BHTS=Btotal
[T]
Jave
[A/mm2]
Stress [MPa]
JavexBAxRmax
Stress [MPa]
JexBAxRmax
2003
2008
2008
BSCCO
20+5=25 T(tape)
20+2=22 T(wire)
31+1=31 T (wire)
89
92
80
125
69
47
175
109
89
2007
YBCO- SP
19+7.8=26.8 T
259
215
382
2008
YBCO-NHMFL
31+2.8=33.8 T
460
245
324
2009
YBCO -SP
20+7.2=27.2
211
185
314
2009
YBCO-NHMFL
(strain limited)
20+0.1= 20.1
241
392
~611
35
f 163 mm
600
open symbols: BSCCO
solid symbols: ReBCO
500
BCF [T]
peak central magnetic field trend
25
300
20
peak winding current
15
10
1990
f 39 mm
400
200
Jave [A/mm2]
30
100
0
2010
YBCO SP 2007 f 87 mm
2000
2005
yearNHMFL
[-]
Slide
12
David Larbalestier
User Committee Meeting, Tallahassee FL November 2-3, 2009
Summary
by Weijers
1995
Bi-2212
f 38 mm
An HEP Collaboration to develop round wire
2212 conductor and coil technology (Arup
Ghosh (BNL) , David Larbalestier (FSU), and
Alvin Tollestrup (FNAL)) - funded August ‘09 at
$4 million over 2 years
Conductor understanding (PIs – Eric Hellstrom (NHMFL) and
Terry Holesinger (LANL)
Conductor mechanical properties – Najib Cheggour (NIST) and
Arno Godeke (LBNL)
Cable development – Emanuela Barzi (FNAL) and Al McInturff
(TAMU/LBNL)
Quench analysis – Soren Prestomon (LBNL) and Justin Schwartz
(NCSU)
Coil Development – Ulf Trociewitz (NHMFL) and Arno Godeke
(LBNL)
Industrial conductor development – Ken Marken (LANL) and Arup
Ghosh (BNL)
Slide 13
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
Rutherford and Roebel cables needed for
large
magnets
Rutherford cable (flattened, fully
transposed cable) works well for round
wire 2212
Major task of the HEP collaboration
YBCO tape cannot be Rutherford
cabled but cabling by the Roebel
method is possible
Predicted perp. field Ic of 15 strand, 5 mm wide
Roebel YBCO cable – parallel 5-7 times higher
YBCO – Nick Long (IRL) and
Andrew Priest (General Cable NZ)
Under evaluation by Karlsruhe and
General Cable and IRL (NZ)
Bi-2212
Arno Godeke, Magnet Group, LBNL
Slide 14
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
Developing the case for a long term
R&D effort 120
Magnet-pull focus
Conductor-pull focus
YBCO coated conductors are
evolving rapidly driven by 40-77K, 03 T use – what about 4 K, 20-40 T
properties?
Bi-2212 is round wire and
multifilament – but has intrinsically
poor vortex pinning due to large
electronic anisotropy
Slide 15
Irreversibility Field (T)
NMR HTS coil
40 T small HTS coil (31 T
background)
Finding the limits (stress, energy
density, quench….)
High current cables (e.g. Zeemans)
100
80
60
Bi-2212 RW
()
YBCO ()
40
MgB2 ()
20
Nb3Sn
Bi-2223 ()
Nb-Ti
0
0
20
40
60
80
Temperature (K)
2212 and YBCO have 3 times the
critical fields of Nb3Sn but their
conductor technology is still
primitive….
What we really want are the vortex
pinning properties of YBCO and the
grain boundary properties of 2212
Why not…………..?
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
Slide 16
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
Timelines and Progress
2006 – Renewal proposal takes up the COHMAG challenge
2007 – experimental concentration on 2212 and formation of HEP
collaborations, first joint SP-NHMFL YBCO coil
Definition of the key problems of the conductor technology and formation
of a focused attack on the issues
New benchmark for a superconducting magnet – 26.8T
2008 – parallel paths for YBCO and 2212 now clearly warranted
32 T all superconducting MRI proposal rejected on technicality (too many
from FSU)
Multilab 2212 proposal submitted from Fermilab (PIs – Larbalestier and
Alvin Tollestrup – BNL/FNAL/LANL/LBNL/NHMFL/NIST
New world record small magnets of 2212 (32T) and YBCO (33.8T)
2009 – recognition that our R&D program was indeed promising
$2M MRI for 32 T awarded (10/09 start, PIs Markiewicz, Larbalestier and
Steve Julian)
$4M awarded by DOE-HEP over 2 years to evaluate the coil-readiness of Bi2212 (6/09 start) PIs Larbalestier and Alvin Tollestrup (Fermilab) with
multilab efforts at BNL, FNAL, LANL, LBNL, NHMFL and NIST
Slide 17
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009
Bi-2212 round wire coil (Trociewitz, Weijers, DCL on Oxford
2212) conductor reached 32.1 T in 31 T background
before HT
after HT
coil specs:
15 mm ID, 38 mm OD
100 mm high
10 layers, 750 turns, 66 m
DB = 1.2 T at 31 T
L ~ 1 mH
• slight discoloration of braid
at enclosed feed-through
• “regular” HT, no visible
leaks
450
400
350
I c (A)
300
250
200
150
100
d = 15 mm
T = 4.2 K
B=5T
unbraided
50
braided
0
0
1
2
3
4
5
6
7
sample #
15mm spiral results
• first HTS wire-wound coil to go beyond 30 T
Slide 18
David Larbalestier NHMFL User Committee Meeting, Tallahassee FL November 2-3, 2009