Operating
Liquid MetalJet X-ray Sources
for Materials ResearchMirko Boin, Roland Mainz, Manuela Klaus, Daniel Apel, Paul Kamm, RobertWimpory, Francisco Garcia-Moreno, Guido Wagener, Christoph Genzel
FLS 2023 Workshop, Aug 27 - Sept 1 2023, Lucerne

OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Microstructure & Residual Stress Analysis @ HZB
Bulk
Neutron diffraction

zE3

SurfaceAcademic training

User service

2

External academic researchers

Materials researchutilizing diffraction &imaging methods

Angle-dispersive lab Xray methods

ψIntermediate zone
Energy dispersive synchrotron Xray diffraction

zEDDI

Lab

OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Microstructure & Residual Stress Analysis @ HZB

E3Academic trainingUser service

3

External academic researchers?

SurfaceAngle-dispersive lab Xray methods

ψLabEDDI

4

OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Prof. Hans M. Hertz & Excillum• Applied Physics at KTH Royal Institute of Technology,Stockholm• Proof of principle with liquid SnPb alloy as anodegreat-great-nephewof Heinrich R. Hertz• Co-founder of Excillum (2007)
Anode alloys: Ga [47-95 wt-%], In [5-37 wt-%], Sn [rest]

grand-son ofGustav L. Hertz

5OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

MetalJet

Installation, Operation &Maintenance6OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

ca. 1.5 m

Installation
X-ray headcathode chamber & jet chamber
under high vacuum (~10-7 mbar)
19” rack components:• System controller• HV controller + generator• Water chiller
Pump box
jet pump (190 bar) + vacuum rough pump
all components: single phase 230 V ~ 16 A
no need for power current or central water supply

7OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Operation

LaB6cathodeFocus
coils

Liquidmetal jet180 µm 

X-raysMin. projected spot size:
5 µm × 5 µm
Line focus @ 250 W emission:
20 µm × 80 µm

8OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Operation

Liquidmetal jet
Ga 95% + In 5%

X-raysRelative Intensity

EKα = 9.2 keVλKα = 1.34 Å102030

Angle-dispersivediffraction•White-beamradiography/
tomography
Energydispersive
diffraction•EKα = 24.2 keV
λKα = 0.51 Å0•40

Energy (keV)

506070

Photon flux [/s/sr/line] at 70 kV/200 W
LineGaKa 9.2 keV
InKa 24.2 keV

Excillummeasured by
PTB & HZB
M. Wansleben et al. (2019)
J. Analytical Atomic Spectrometry 34(7) 1497-1502
doi: 10.1039/C9JA00127A

9OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Maintenance

LaB6 cathode

Exit window

Particle filter

NozzleTarget alloy+ jet pump & vacuum pump parts (gaskets, oil, valves), water cooling…

10OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

MetalJet D2 @ HZB

70/160 kV max. 250 W
furnaceload frame

PVD

detectors….

11

OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Primary optics
Slits /
Collimators

SampleDetectorCu(In,Ga)Se2 112

Montel optics• e.g. monochromatic
Ga Kα radiation• available at HZB
since 2021

10 s
Polycapillary optics

Polycapillary

SampleDetectorCu(In,Ga)Se2 112

0.2 s

12OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

MetalJetApplication examples

13

OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Phase-transitions in PV materials
γ phaseβ phaseα phaseCsPb(BrxI1-x)3sample

δ phaseIntegrated diffraction pattern as a function of temperature
for CsPb(BrxI1-x)3 with x = 0.23

Time resolution down to 0.2 s possible!

H. Näsström, P. Becker, J. Márquez, O. Shargaieva, R. Mainz,
E. Unger and T. Unold. J. Mater. Chem. A (2020), doi: 10.1039/D0TA08067E

14OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Long-term in-operando studies of LiS batteries• cathode: sulfur loaded CNTs
• anode: lithium• discharge: forming of Li2S2• charging: decomposing to Li2S + S
polycapillary

more than 3 weeks
non-stopmeasurement• sulfur diffraction line intensities• domain/crystallite size

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OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Residual stress analysis

MetalJet D2 @ 160 kV + Ge Detector

GDTDTD16OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCHWhite-beam Imaging

MetalJet D2 (70/160 kV)• Full cone beam & full energy spectrum• Detector choice depends on sample attenuation•AM Structure

Tomography

DectrisPilatus

Metaljet + CMOS

Si photon-counting

0.5 s
5s
W-Microfocus + Flatpanel

Advacam
Medipix
CdTe photon-counting

Hamamatsu
flat panel

5s

CsI scintillator plate

0.5 s

Polymer foams
C. Jiménez et al., (2015)

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OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Conclusion,Review & Outlook

OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Conclusion

SurfaceAcademic training

User service

18

External academic researchers

Materials researchutilizing diffraction &imaging methods

Intermediate zone
Energy dispersive X-raydiffractionzAngle-dispersive lab Xray methods

ψ19

OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Review On Performance & Limitations
2003

SnPb alloy, 100 W, 50 kV, 150 µm focus

2007

Ga-based alloys (liquid at room temperature)
MetalJet D1, 70kV, 100 W / 200 W

2011

MetalJet D2

2015200 W  250 W

2019

Dynamic Adaptation Upgrade

www.excillum.com

Extending cathode lifetime
24/7 operation
Theory:Higher jet heat-load capacity & boiling point of Ga >2000 °C

Practice:

Evaporation effects  possible vacuum issues
More emission power  bigger focus spot (under same distance)
Higher brightness  Compact device  careful balance of vacuum/temperature/jet

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OPERATING LIQUID METALJET X-RAY SOURCES FOR MATERIALS RESEARCH

Outlook… at HZB in 2023

MetalJet E1
160 kV 1000 W

Thank you verymuch for yourattention!
Do not hesitate to contact us:

boin@helmholtz-berlin.de
Expected intensity gain: 4x