High resolution X-ray CT as enabling

technology for material research

Veerle Cnudde Dept. of Geology & Soil Science - UGCT, Ghent University, Belgium

With credits to the entire UGCT team (www.ugct.ugent.be)

Sedimentary and Engineering Geology (Dept. of Geology and Soil Science)

• Prof. Dr. Veerle Cnudde • Dr. Hannelore Derluyn • Dr. Victor Cardenes • Dr. Jan Dewanckele • Drs. Tim De Kock • Drs. Marijn Boone (UGent/VITO) • Drs. Wesley De Boever • Drs. Tom Bultreys • Drs. Jeroen Van Stappen • Drs. Delphine Vandevoorde (UGent/UA) • Danielle Schram

UGCT : Centre for X-ray tomography http://www.ugct.ugent.be/

Radiation Physics research group (Dept. of Physics and Astronomy)

• Prof. Dr. Luc Van Hoorebeke • Dr. ir. Manuel Dierick • Dr. ir. Matthieu Boone • Dr. Bert Masschaele • Drs. Jelle Dhaene • Drs. ir. Thomas De Schryver • Dra. Amelie De Muynck • Ir. Pieter Vanderniepen

Laboratory of Wood Technology (Dept. Forest and Water Management)

• Prof. Dr. ir. Joris Van Acker • Dr. ir. Jan Van den Bulcke • Drs. ir. Wanzhao Li

UGCT : Centre for X-ray tomography

XRE Inside Matters

http://www.ugct.ugent.be/

www.insidematters.eu http://www.xre.be/

UGCT : Centre for X-ray tomography

• Perform research on and with high resolution X-ray CT

• Control and optimize complete workflow

– Hardware: custom designed and built CT scanners

– Hardware: peripheral equipment (climate chambers, pressure stage ...)

– Software: scanner operation

– Software: tomographic reconstruction (Octopus)

– Software: 3D analysis (Morpho+/Octopus Analysis)

• Applied material research for the characterization of wood, stone, concrete, plastics, foams, food, metal, biological material, ….)

www.octopusimaging.eu

What is X-ray micro-tomography?

(1991, John O’Brien, the New Yorker Magazine)

X-ray source

Sample

X-ray detector

Tomography: the principle

dExEµEIIi

ii

)(exp0

X-ray source

Sample

X-ray detector

Tomography: the principle

sMM

dR

11

SOD

SDDM

R: Resolution

d: resolution detector

s: spot size X-ray source

M: magnification

Realisations by UGCT

Van Vlierberghe et al. , 2007. Biomacromolecules 8(2):331-337.

Dhondt et al , 2010. Trends in Plant Science

15(8):419-422.

Masschaele et al., 2007. NIMA 580(1):266-269.

Dierick et al., 2014. NIMB 324:35-40.

Van den Bulcke et al. , 2008. International biodeterioration and Biodegradation.

Boone et al., 2011. Geosphere. 7(1);

79-86.

Realisations by UGCT

HECTOR (2012) • High power, high voltage directional tube

(240kVp, 280W), focal spot size down to 4µm • Large flat-panel detector (40²cm²) • Fast scanning

See also: B. Masschaele et al., J. Phys. Conf. Series. 463 (1), (2013)

Source : directional open tube

kVmax : 240 kV

Pmax : 280 Watts

Focal spot : 4 µm (nominal)

Detector : Perkin Elmer aSi flat panel

FOV : 40cm x 40cm

pixel count : 2000x2000

pixel pitch : 200 µm

source-detector range : ~2m

Sample stage : Rotational error : ~1µm

Max. sample weight : 80 kg

source-object range : ~2m

vertical (helical)range :~1m

HECTOR (2012)

Subsample A (4 µm resolution) discrimination of mineral grains and pore space

Subsample B (2.8 µm resolution) discrimination between different minerals (quartz, feldspar, clays) Microporosity visible

Sample size Resolution

EMCT (2012) • Gantry based system

• Environmental control (Temperature, pressure, ...)

• Continuous scanning

• Ultra-fast scanning (<30 sec)

• Maximum resolution 5µm

Dierick et al., Nucl. Inst. & Meth. 324 (0), (2014)

Source :

directional closed tube

kVmax : 130 kV

Pmax : 39 Watts

Focal spot : 5 µm (nominal)

Detector :

CMOS flat panel

pixel count : 1316x1312

pixel pitch : 100 µm

source-detector range : 15-40cm

Sample stage :

Rotational error : <3µm

Max. sample weight : 50 kg

source-object range : ~2m

vertical (helical)range : ~1m

X-ray CT add-on modules

Pressure Cell (120 bar) Freezing Cell (-20°C) Climatic chamber Pressure/tensile stage

Acquiring, or developing extra add-on modules, such as an in-situ tensile/compression cell.

- Porosity calculation - Labeling different pores according

to: - size - orientation - surface - … - Pore network extraction - Pore throats location and

characteristics

Image analysis: 3D pore/grain characterization

Pore Network Modelling for

multi-phase flow

Mineral grains

Pore space

Prediction of macroscopical behaviour based on microscopical study (PNM)

Water displaced by non wetting phase

APPLICATIONS OF HIGH RESOLUTION X-RAY CT AS CHARACTERIZATION AND MONITORING TECHNIQUE

(a)

(c)

(b)

(d)

Mšené sandstone + halite crystals (red) (a-b) after 1st cycle of wetting and drying at 20%RH and (c-d) after 2 additional cycles.

Salt precipitation migration into pores close to surface controlled by RH cycling

How does salt crystallization looks like in 3D? 3 molal Na2SO4-solution from room t°cooled to 0°C => sodium sulfate heptahydrate crystallization Scans taken continuously during 19 minutes at a rate of 1 scan/80 s (pixel size: 24 µm).

Dynamic Imaging: climatic chamber

Monitoring internal changes due to external chemical changes

Before acid test After 6 days

Dewanckele, et al. 2014. Materials Characterization 88: 86–99.

.

Dynamic Imaging: freezing cell

Semi-saturated conditions

B

CO2

18 scans in total Total period: 14 hours Each scan: 2’20” Resolution: 18 µm Total porosity: 42.5 % brine: 35.4% CO2 : 7.1%

Dynamic Imaging: wollastonite (CaSiO3) carbonatation

Semi-saturated conditions

CO2

CaCO3

Dynamic Imaging: wollastonite carbonatation

Chemical + structural info

• Currently a new scanner is under development: XRF-CT scanner Heracles => Combines micro-CT scanner with XRF detectors (detect characteristic radiation that comes from a sample being irradiated with X-rays => allowing to identify the elements in it).

Biotite magnetite Zircon

SR-µ-XRF

micro-CT

+ +

2D-µ-XRF CT-µ-XRF

~ 3

.5 m

m

Conclusions:

- HRXCT is an ideal 3D characterization technique

- a wide range of new and dynamic experiments are

now possible using lab-based HRXCT

- spatial and temperal resolution are still increasing

- besides on the hardware level, also on the software

level progress is being made

Thank you for your attention!

Prof. Dr. Veerle Cnudde

veerle.cnudde@ugent.be

Department of Geology and Soil Science - UGCT, Ghent University, Krijgslaan 281/S8 9000 Ghent

Belgium

0032-9-2644580

Special thanks to: Entire UGCT team

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