magnetic materials in sustainable energy · rare earth metals, recycling magnetocaloric materials...
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O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Oliver GutfleischLeibniz Institute for Solid State and
Materials Research, IFW Dresden, Germanyfrom 01.02.2012 @ Technical University of Darmstadt
AND Fraunhofer Group Substitutional Materials Hanau
� Materials for Energy Applications
� Magnetism and Energy:� Permanent magnets for E-mobility and wind turbines
� Rare earth metals, recycling
� Magnetocaloric materials for novel refrigeration tec hnology
� Description of structure, dynamics of phase transit ions and function on all length scales
Magnetic Materials in Sustainable Energy
Adv. Mat. (Review) 23 (2011) 821-842
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Renewable Energy is intermittent in nature
SEASONAL CYCLE
LATITUDE
I
YEAR
I
DAY
I
DAY/WEEK
I
DAY - NIGHT CYCLE
Geographical ENERGY DISTRIBUTION of WWS
RESIDENTIAL Heat
STORAGE
TRANSPORT
MOBILITYWork
CONVERSION of WWS
CONVERSION into …
INDUSTRY Heat & Work
adapted from A. Züttel
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Materials for sustainable energy
commodity materialsdisposible fuels
gas CH4oil CH 2
coal CH 0.8
heat useful work
combustion
sunlightwind water
geothermalbiomass
electricitybiofuel
hydrogenchemical fuel
useful work
Direct conversion
material + chemistryultra-small and -fast
modelling nano-science complex materials
BUT: critical metals
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
ENERGY CARRIERS
1
10
100
1000
10000
100000
0.001 0.01 0.1 1 10 100Energy density [kWh/kg]
Ene
rgy
dens
ity [k
Wh/
m3]
Pb-acidbattery
Li-ionbattery
mag. coil
EDLC comp. air
hot water
biomass
coal
oil
fusion
fission
hydrideshydrogenstorage
capacitor
hydro-power hydrogen
natural gas
flywheel
3
ultimatebattery
NH3
GRAVITATION
ELECTROSTATIC
NUCLEAR
CHEMICAL
ELECTROCHEMICALINERTIA
A. Züttel et al. , Phil. Trans. R. Soc. A (2010)
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Permanent magnets for e-mobility and wind turbines
simulation
thermomechanicaltreatment
Characterisation with atomic resolution
grain boundary engineering
raw materialsrecycling
texturemicrostructure
stability
magneticinteraction
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Intrinsic and extrinsic magnetic properties
saturation polarisation, Js
anisotropy field, Ha
Curie temperature, TC
intrinsic properties
microstructure
100µm > l > 1nm
↔ fit µ-magnetic length scales
+
dc: critical single-domain particle size
δδδδwδδδδw: domain wall width
remanence, Jr
coercivity, Hc
energy density, (BH)max
extrinsic properties⇒
J or B
Jr or Br
Hc
Hc
compound T C , K µ0Ms, T K1, MJ/m 3 dc, nm δδδδw
Nd2Fe14B 585 1.60 5 214 4
SmCo5 993 1.05 17 1700 3.7
Sm2Co17 1100 1.30 3.3 490 8.6
α-Fe 1043 2.16 0.046* 7 30
J. Phys. D: Appl. Phys. 33 (2000) R157-R172
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Sintered NdFeB magnets for electro motors� Design light-weight, high torque-to-weight ratio mo tors , using
permanent magnets with adequate temperature stability
���� torque scales linearly with remanence
Adv. Mat. (Review) 23 (2011) 821-842
Courtesy: Toyota Motor Corporation
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
-4 -2 0 2 4-1,5
-1,0
-0,5
0,0
0,5
1,0
1,5
pola
risat
ion
J (T
)
applied field µ0H (T)
Texture in NdFeB sintered magnets
Nd Fe B
macrotexture ↔ microtexturemagnetic measurements ↔ Kerr microscopy
Nd2Fe14B
5µm
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Magnetisation reversal in sintered NdFeB
200 nm
efficient use of Dy bygrain boundary diffussion process
coating
the weak link
Nd2Fe14B (Φ)
Nd1.1Fe4B4 (η)Nd2O3pore
5µmNd-rich intergranular phase
Hc = HA
Perfect materials: Coherent rotation
H
K
Hc << HA
Defects :Nucleation + propagation
activation volume
K
Nucleation-type magnet
crystalline or amorphousmetallic or oxidic
FM or PMmicrochemistry, structural defects
continuous or discontinuous
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Atom model Simulated image Real image
Fe, Nd, B
10 Å
Nd2Fe14B <001>
Nd2Fe14B <001>
Sample thickness: 15 nm
- Nd2Fe14B, zone axis: <1-40>
1Å resolution by C s aberration corrected HRTEM
Nd Fe B
Multiscale characterisation III
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Atomistic simulation of Nd-rich phase / Nd2Fe14B interface
[110]
[1-10]
[120]
[210]Nd2O3-hP5
Nd2Fe14B
Fourier enhanced HR-image
���� Thickness of region with reduced anisotropy varies with phase and orientation
Distorted region
Appl. Phys. Lett. 97 (2010) 232511, cooperation Uni Sheffield
Magnetoelastic anisotropy as function of distance for Nd2Fe14B (100) surface cut, c-axis parallel to interface to a fcc Nd (011) surface, the plane orientation is in respect to the interface. Inset: Top layer is the fcc Nd rich phase, bottom layer is the Nd2Fe14B phase.
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
� The motor/generator in a hybrid electric vehicle contains 2 kg of NdFeB . This application is set to grow to between 10million and 20million vehicles by 2018.(now: 2.5 out of 850 million vehicles are hybrids worldwide)
� New designs of wind generators use NdFeB magnets at a rate of ~700 kg per mega-watt . This application alone has potential to increase RE demand by 25% per year above current production.
� Hard disc drives cannot function without RE permanent magnets. Formerly 70% of the NdFeB market this is now diluted by the other major applications.
� World production of sintered NdFeB in 2011: ~100.000 t
� Solid state energy efficient cooling: Magnetocalorics
Permanent Magnet Growth
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
References in Adv. Mat. (Review) 23 (2011) 821-842
Installed wind power doubles every three years…
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Rare Earth Minerals
Science News, August 27, 2011
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Science News, August 27, 2011
Rare Earth Elements in Automotive
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Pr, 6.60%
Ho-Tm-Yb-Lu, 0.00%
Y, 20.00%Er, 1.80%
Dy, 3.60%
Tb, 0.60%
Sm, 5.20%
Gd, 4.80%
Eu, 0.70%
Ce, 1.90%
La, 30.40%
Nd, 24.40%
Rare earth oxides in China
Southern Clay
Baotou & Shandong:
Light RESichuan
Area: Light RE
Southern China:
Heavy RE
Pr, 5.10%
Ho-Tm-Yb-Lu, 0.80%
Y, 0.20%Er, 0.01%Dy, 0.01%
Tb, 0.01%
Sm, 1.20%
Gd, 0.70%Eu, 0.20%
Ce, 50.07%
La, 25.00%
Nd, 16.70%
Baotou Bastnasite
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
$-
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Nd Metal $28 $28 $28 $31 $37 $45 $45 $44 $34 $35 $35 $34 $32 $36 $39 $37 $34 $32 $31 $26 $23 $22 $20 $15 $15 $15 $15 $16 $15 $15 $17 $18 $18 $22 $23 $26 $31 $31 $34 $35 $35 $38 $42 $44 $47 $51 $50 $51 $62 $74
Pr-Nd Metal $27 $27 $28 $29 $34 $43 $43 $39 $31 $30 $30 $29 $27 $31 $32 $31 $29 $29 $28 $23 $21 $21 $19 $13 $13 $13 $14 $14 $14 $14 $16 $16 $16 $21 $21 $24 $29 $29 $32 $33 $33 $35 $37 $39 $41 $43 $42 $42 $49 $60
Raw Materials: Nd and Pr-Nd metal (Asian Metal and metal-pages)
$/kg
50
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2007 2008 201120102009
International Herald Tribune, May 4, 2011„rare earths prices skyrocket“
Nd 283 $/kg, Sm 146 $/kg, Dy 900 $/kg470 $/kg
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
UK Magnetics Society Newsletter Cover Winter 2010 Science News, August 27, 2011
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
• Meeting in 09/2010 at the German Ministry for Environment, a priority list for critical materials was determined. First Priority was given to:
• Dy• Nd• Tb• Pr• Ga (Magnets 0.1%, Power Electronics, DC/AC Converter)• In (Heating/Cooling, Electronics, Displays)• Pd (Fuel Cell, Cat., Power Electronics, Battery-Management-System)• Pt (Fuel Cell, Cat., Power Electronics, Battery (Au-Pt Cat. In Li-Air Batt.))• Au (Fuel Cell, Cat., Power Electronics, Battery (Au-Pt Cat. In Li-Air Batt.))• Cu (Electronics, Cables, Battery, Cooling/Heating,…)• Ru (Semi-Conductors, Capacitor, Fuel Cell, Battery) – all in mg volumes
• Dy was described to become the most critical element of all because of single source in the Chinese region and extremely low content in the mines of Molycorp and Lynas.
• After 2014 a sufficient amount of RE (beside Dy) ca n be expected in the global market.
• Dy will NOT suffice !
Rare metals in electro mobility
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Recycling of scrap sintered NdFeBby hydrogen processing
(1) HD – hydrogen decrepitationand
(2) HDDR – hydrogenation disproportionationdesorption recombination
Issues
• Removal of brittle intermetallics imbedded with epoxy in assemblies
• Powders are very reactive
• Organics from machining, coatings and epoxies
• Coatings (e.g. Ni) for corrosion protection
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
HDDR
Nd2Fe14B + ½ xH 2 ⇔⇔⇔⇔ Nd2Fe14BHx ± ∆∆∆∆H1 (HD)
Nd2Fe14B + (2±x)H2 ⇔⇔⇔⇔ 2NdH2±x + 12Fe + Fe2B ± ∆∆∆∆H2
0.03 –0.13 MPa
H2
vac.5 kPa
H2
T
t
d-HDDR
T
pNdNdNdNd2222FeFeFeFe14141414BHBHBHBHxxxx NdHNdHNdHNdHxxxx
FeFeFeFeFeFeFeFe2222BBBB
texture memory effect texture memory effect texture memory effect texture memory effect Br >> Js/2
100 µm 300 nm
Hydrogen decrepitationHydrogen decrepitationHydrogen decrepitationHydrogen decrepitation
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
after HD after d-HDDR
Polyhedron single crystal particle ultrafine grained structure ~~~~300nm
Morphology of hydrogen recycled magnet
139.5
1.93
0
20
40
60
80
100
120
140
160
10 30 50 70 90 110 130
Hydrogen Pressure /kPa
BH
max
/kJ/
m3
0.0
0.5
1.0
1.5
2.0
2.5
μ0Hc /T
BHmax
μ0Hc
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Weight: 465 gVolume: 110 cm 3
Motor power: 50 WMagnet weight : 80g
Weight: 295 g ( -37%)Volume: 54.5 cm 3 (-51%)Motor power: 50 WMagnet weight : 20g
conventional seat motorusing ferrite magnet
new seat motor usinganisotropic polymer bonded
HDDR magnet
Energy saving by size reduction
photos courtesy Aichi Steel
latest motor usinganisotropic polymer bonded
HDDR magnet
Weight: 140 g ( -53%)Volume: Motor power: 50 WMagnet weight : 8g
Adv. Mat. (Review) 23 (2011) 821-842
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
PATH 1 – use of existing phases
• Dy-less magnets – GBDP, grain refinement, interfacial control
• Textured nanocomposites (bottom-up approaches incl. the consolidation of nanoparticles, core-shell particles, etc)
� Reduction, Substitution and Recycling of RE-TM magn ets, reduce losses
on-going cooperations between us and Japanese partne rs
PATH 2 – “new” better “alternative” phases
• Search for new phases (Heusler, Mn3Ga, MnBi, Fe16N2, etc)
• FeCo (or similar, induce tetragonality or other lower symmetry, explore shape anisotropy)
• from metastability to volume samples
���� Aim to be (much) better than best hard ferrites wit h good thermal stability but without RE
How to move forward ?
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
180 200 220 240 260 280
0
5
10
15
20
25
30
35
0 ~ 5 T
LaFe12Si LaFe11.8Si1.2
LaFe11.57Si1.43
LaFe11.4Si1.6
LaFe11.2Si1.8
|∆S
| (J/
kg K
)
T (K)
Solid state energy efficient magnetic cooling
compact, solid state, silent and energy efficient heat pump
10 µm
Magnetic Materials and Devices for the 21 st Century: Stronger, Lighter, and More Energy Efficient
Adv. Mat. (Review) 23 (2011) 821-842
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
All refrigeration technologies have one thing in common: they contain a refrigerant which changes state, and in doing so, changes temperature. The changes in temperature of the refrigerant are relayed to the body to be cooled by means of one or more heat exchangers.
Magnetic refrigeration is the only alternative tech nology which would simultaneously eliminate the need for harmful refri gerant gases and reduce the energy requirements, and hence carbon dioxide e missions.
2 www.coolchips.gi3 www.coolchips.gi, www.healthgoods.com4 F.J. DiSalvo, Science, 285 703 (1999) and references therein5 D.L. Gardner and G.W. Swift, J. Acoust. Soc. Am., 114 1905 (2003)6 C. Zimm et al., Adv. Cryog. Eng. 43 1759 (1998)
Solid state energy efficient magnetic cooling
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Magnetocaloric effect & Magnetic refrigeration
T
H
T+∆∆∆∆Tapply field
TT-∆∆∆∆T
expel heat �”isothermal”
H
remove field
∫
∂∂=∆
H
0 Hm
dHTM
S
dHT
M
C
TT
H
0 pH,pH,∫
∂∂−=∆
Large H
Large HT
M
∂∂
Small CH,p
Large MCE
adiabatic
adiabatic
� Maxwell equation applies to equilibrium thermodynam ics� δδδδM / δδδδT finite or infinite during a first-order magnetic phase transition ?� hysteresis � coupled magnetostructural transitions and related l atent heat� comparison with c p (H) measurements
absorb heat
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
RCP = B(M2-M1) per refrigeration cycle
Relative cooling power RCP
Actual cooling power [W/m 3]:RCP x operating frequency fInertia of heat exchange � upper limit 200 Hzanddynamics of the 1st-order phase transition
with M 2 > M1and ∆∆∆∆T (S1-S2) = B(M2-M1)
Magnetic refrigerant undergoing a 1st phase transition:(a) free energies of the two phases in the absence of magnetic field(b) field-induced entropy change plotted against T.
Phys. Rev. B 76, 092401 (2007)APL 90, 251916 (2007)Cooperation with IFW theory group M. Richter
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Requirements and Challenges
� strong temperature dependence of magnetisation, large entropy jump at T C, large field dependence of T C
� large ∆∆∆∆Tad / ∆∆∆∆H ���� driven by moderate magnetic field (RPMs) at a tailored operating temperature
� small thermal and magnetic hysteresis, dynamics
� material cost (e.g. Gd), non-toxic (e.g. As)
� high thermal and small electrical conductivity
� mechanical and chemical stability, high ductility
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
alloy Tc (K) structure ∆V problems
Gd5(Si1-xGex)4 130-270 orthorhombic⇔monoclinic
0.5 % high purity Gd
Giant magnetocaloric materials
Pecharsky and Gschneidner Jr., PRL 78 (1997) 4494
Gd5Si2Ge2 0 - 5 T
Gd 0 - 5 T
Gd 0 - 2 T
Gd5Si2Ge2 0 - 2 T
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
alloy Tc (K) structure ∆V problems
Gd5(Si1-xGex)4 130-270 orthorhombic⇔monoclinic
0.5 % high purity Gd
La(Fe,Si) 13Hxalso Si or Co
200-330 cubic ���� cubic(NaZn13)
1.5 % αααα Fe
MnFe(P,As)MnFe(P,Ge)
150-340250-580
hex � hex(Fe2P)
0.1 % toxic
MnAsMn(As,Sb)
317reduced hysteresis
hex � ortho(NiAs�MnP)
2.2%0.7 %
toxic
Ni55.2Mn18.6Ga26.2
NiMnInCo315
various
L21 ⇔ 5Mmartensitic trans.
0 large strain,hysteresis
Giant magnetocaloric materials
3d intermetallic compounds as an alternative to heavy rare earths containing compounds ??(high abundance, relatively high magnetic moment, coupling to lattice)
in red: research @ IFW Dresden
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
La(FeSi)13
La: 8a sites Fe/Si: 8b and 96i
NaZn13-type structure stabilised by Si or Al
−)3( cFm
(1) What is special about La(Fe,Si) 13
(2) Synthesis
(3) Tailoring hysteresis and operating temperature
(4) Magnetovolume, hybridisation and cooling power
(5) Strain related effects
(6) Layered beds
Research @ IFW Dresden
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
La(Fe,Si)13Hx
Hydrogen insertion
• Tc ↑↑↑↑• 1st order transition preserved – large ∆∆∆∆Smax
Co substitution
• Tc ↑↑↑↑• gradual transition to 2nd order – ↓↓↓↓ ∆∆∆∆Smax
J. Magn. Magn. Mat. 320 (2008) 2252
JAP 102 (2007) 053906
Tailoring Tc by interstitial hydrogen
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
∆∆∆∆Tad and ∆∆∆∆V/V of LaFe 11.7Si1.3
160 165 170 175 180 185 1900
1
2
3
4
5
6
7
∆V/V
, %
∆Tad
, K
T,K
LaFe11.7
Si1.3
µ0H=1.9T
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
1,0
adiabatic temperature change and related magnetovol ume effects
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
New porous morphology of LaFe 11.6Si1.4
BulkHP @ 625°CHP @ 575°C
Hot pressed porous compacts retain mechanical integ rity during temperature-field cycling
Adv. Mat. 22 (2010) 3735, Patent filed.
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
180 200 220 240 260 280 300 320 3400
1
2
3
4
5
6
7 µ0H = 1.9 T
LaFe11.74
Co0.13
Si1.13
LaFe11.40
Co0.52
Si1.09
LaFe11.05
Co0.91
Si1.04
LaFe10.71
Co1.30
Si1.00∆T
AD, K
Temperature,K
LaFe11.6
Si1.4
260 270 280 290 300 310 320 330 340 3500
1
2
3
4
5
La(FeSi)13
HX
µ0H = 1.9 T
LaFe11.05
Co0.91
Si1.04
LaFe10.71
Co1.30
Si1.00
∆TA
D, K
Temperature,K
Gd
Comparison of ∆∆∆∆Tad
1st vs. 2nd order type materialsEU project SSEEC, cooperation Vacuumschmelze Hanau
���� comparison in a realistically operating prototype d evice
refrigerant capacity
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Towards applicationPrototype development in the SSEEC project (EU)
15 K span with single alloy35 K span with multi-alloyregenerator achieved
Plates of sintered La(FeCoSi) 13 of 0.25mm thickness
produced by Vacuumschmelze Hanau /System by Camfridge Ltd.
and 1.2 Tesla
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Generally, we have a number of parameters to maximize the MCE at a given magnetic field:
• Lattice (especially for low magnetic fields the way forward is to maximize the structural contribution; big shift of the magnetostructuraltransition with field (several Kelvin per Tesla))
• Spins (exploit chemical complexity to precisely tune magnetism)
• Hysteresis (maintain first-order character but minimize hysteresis)
• µ-structure (engineer (multiphase) nanostructure with stress generating/relieving features)
• Metastability and non-equilibrium (coexistence)
How to move forward ?
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Drastically Reduced Rare Earth use in Applications of Magnetocalorics
• minimise rare earth wastage through the efficient manufacture of large volumes of magnetocaloric material parts;
• drastically reduce the consumption of rare earth permanent magnets in end use through step-change improvements in the performance of magnetocaloric materials;
• investigate the fundamental properties of several rare earth-free magnetocaloric materials through theoretical modelling, resulting in improved understanding of magnetocaloric mechanisms and parallel benefits for thermomagnetic power generation.
How to move forward ?
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
October 2011
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Abundance of rare earths
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Rare earth value chain
Courtesy P. Dent, MMM Conf. Nov. 2011
O. GutfleischMagnetic Materials in Sustainable Energy
EU_JAPAN Expert ´s workshop on Critical Metals 21-11-2011
Manufacturing of sintered RE magnets
Courtesy P. Dent, MMM Conf. Nov. 2011