X-ray and neutron diffraction on laser heated levitated samples:
successes and challenges
Sergey V. Ushakov, Alfred J. Pavlik, Alexandra Navrotsky
Richard J. K. Weber
Chris J. Benmore
Joerg C. Neuefeind
Ele
me
nts
min
sp
ecif
ic g
rav
ity
max melting temperature °C
2000 3000
carb
ides
inte
rmeta
llic
s
oxi
des
bo
rid
esn
itri
de
s
silic
ates
sulp
hid
essi
licid
es
20
10
7
5
3
2
30
Silic
ate
s
Sr SiO2 4
Ca SiO2 4
Mg SiO2 4
2000
2500
3000
3500
Su
lfid
es
CeS
ThS
HfS
Pr S3 4
PrS
Hf Si3 2
MoSi2
Mo Si5 3
Sil
icid
es
Ta Si5 3
W Si5 3
Zr Si5 3
Hf Si5 3
TaSi2
V Si5 3
C
W
Re
Os
Mo
Ru
Ir
Nb
BHf
Carb
ides
HfCTaC
NbC
ZrC
Ta C2
Ta C2
WCW C
2
ThC2
ThC
SiC
VC
MoC
PrC2
UC2
B C4
GdC2
V C2
Ni C3
La C2 3
Nit
rid
es
HfN
TaN
ZrNBN
TiN
UNThN
Nb N2
AlN
NbNVN
Th N2 3
Ta N2
Bo
rid
es
HfB2
TaB2
ZrB2
WB
TiB2
WB2
ZrB
Mn B3 4
Ta B3 4
UB4
LaB6
VB2
UB2
TaB
NdB
ThB4
Mo B2
CeB6
CrB
Ox
ides
ThO2
HfO2
UO2
ZrO2
MgO
CaO
BeO
Sc O2 3
Y O2 3
La O2 3
Al O2 3
Gd O2 3
Cr O2 3
MgAl O2 4
Re W3 2
Re Ti2 4 5
Mo Al3
OsTa3
HfMo2
Al Mo2
Inte
rMe
ReW
OsTi
IrTa
RuZr
WPt
Ir Nb3
Ir Ti3
Me
ltin
g T
em
pe
ratu
re,
°C
High temperature ceramics for aerospace and nuclear applications
Calculation of Phase Diagrams (CALPHAD) methods rely on thermodynamic data for compounds and their alloys / solid solutions
FactSage, MTDATA, PANDAT, MatCalc, JMatPro, Thermo-Calc
1980 1990 2000 2010
50
100
150 CALPhaD
first principles phase diagrams
Nu
mb
er
of
pu
blic
atio
ns
Year
Thermodynamic data from high-T diffraction
Molar volumes as a function of temperature
DV for solid state phase transitions
DSc for order - disorder transitions
In situ phase diagram determination
0.3
0.4
0.5
0.6
0.7
0.2
Laser flashRonchi et al. 1999
Ronchi et al. 1993
UO2UO2
T1
T
Nd-YAG
Nd-YAGT2
ME
LT
ING
W
Temperature, °C
He
at
cap
acit
y (
J/g
·K)
1600 2000 2400 2800 3200 3600 4000 4400 4800
10
15
20
Cp
/R
Phase transitions in RE2O3
Ho O2 3
Lu O2 3
Yb O2 3
Tm O2 3
Er O2 3Y O2 3
Dy O2 3
Tb O2 3
Gd O2 3
Eu O2 3
Sm O2 3
Pm O2 3
Nd O2 3
Pr O2 3
Ce O2 3
La O2 3
A
B
C
H
X
Liq
2000 2500Temperature, °C
Ionic radius R
E (C
N=6
), Å
3+
0.85
1.05
NSF DMR 1506229 Phase Transitions in RE2O3 above 2000 °C
Aerodynamic levitators with laser heating
SNS NOMAD BL1B
Joerg Neuefeind Chris Benmore
CO laser10.6 µm
2
X-ray beam0.139397 Å
Richard Weber
APS 6-ID-D
2 4 6 8 10
0.1 s exposure time 60 summed exposures Cubic ZrO2 T app = 2900 °C a = 5.283 Å
APS 6-ID-D 6 seconds collection time
6 seconds collection
XRD data collection CO laser10.6 µm
2
X-ray beam0.139397 Å
Bank 1
Bank 2
Bank 3
Bank 4
Bank 5
ND data collection
Levitated Y2O3 at RT 30 minutes
SNS NOMAD BL1B
Data Processing
Calibration at RT for every levitating bead
Integration with FIT2D, refinement with GSAS/ExpGUI, FullProf, GSAS-II
Le Bail refinement of cell parameters for high temperature H phases in Y2O3, Er2O3, Ho2O3
Refinement of room temperature structures on
levitated samples to validate the method
ND of levitated La2Zr2O7 at RT, BANK 3, Rietveld fit
a 10.8133(3)
x(O) 0.3305 (1)
100*UISO Å
La 0.65(4)
Zr 0.34(4)
O 0.84(3)
0.10(3)
χ2 2.75 Rwp 4.8% RF
2 4.3 %
Results from 3 days of diffraction experiments on levitator at APS (June 15-17, 2011)
Y2O3 transforms in H-type before melting in Ar and O2. Volume reduction on C-H phase transition was refined.
Pyrochlore structure of La2Zr2O7 persists to the melting temperature. Thermal expansion was used to validate high temperature ab initio calculations.
Thermal expansion of Eu2O3-ZrO2 DF solid solutions and anti-site occupancies on pyrochlore-DF phase transition in Eu2Zr2O7 were refined.
Maram PS, Ushakov SV, Weber RJK, Benmore CJ, & Navrotsky A (2015) J. Am. Ceram. Soc. 98 (4), 1292
Hong Q-J, Ushakov SV, Navrotsky A, & van de Walle A (2015) Acta Mater. 84, 275
Ushakov SV & Navrotsky A (2012) J. Am. Ceram. Soc. 95, 1463
CO laser10.6 µm
2
X-ray beam0.139397 Å
10.45
10.50
10.55
10.60
10.65
10.70
10.75
10.80
10.85
1000 2000 3000
a, Å
Temperature, °C
Lu2O3
Yb2O3
Er2O3
Ho2O3
4
5
6
7
8
9
10
11
12
TEC
, 10
-6/°
C
Lu2O3 Yb2O3 Er2O3 Ho2O3
Thermal expansion of C-type RE2O3 in Oxygen flow
Alfred Pavlik, Summer 2015
Pre-melting C-H phase transition in Er2O3 in Ar
H-type Z=1
C-type Z=16
Y2O3 DV -3.1% Er2O3 DV -3.4% Ho2O3 DV -3.9%
C-H pre-melting phase transitions RE2O3
Neutron Diffraction results (Aug 23-29, 2014)
Ushakov, S. V., Navrotsky, A., Weber, R. J. K. and Neuefeind, J. C. (2015), Structure and Thermal Expansion of YSZ and La2Zr2O7 Above 1500°C from Neutron Diffraction on Levitated Samples. J. Am. Ceram. Soc., 98: 3381
YSZ La2Zr2O7
0.31
0.32
0.33
0.34
0 500 1000 1500 2000 2500x
(O, 4
8f)
Temperature, °C
Conclusion
Refinement of high temperature structures is possible from X-ray and neutron diffraction on laser heated levitated samples using existing instruments at APS 6-ID-D and SNS NOMAD*
*Thermal gradient of ~150 °C in diffraction volume
http://thermo.ucdavis.edu/
Confirmed Invited speakers: Dario Manara, ITU Elizabeth Opila, University of Virginia Richard Weber, MDI Lawrie Skinner, Stony Brook
UC Davis workshop on
Structure and Thermodynamics of oxides at High Temperature
October 18-21, 2016 (before MS&T 2016 and ACerS 118th meeting in Salt Lake City)