WELCOME

Department MTM,

MATERIALS PERFORMANCE AND NON-DESTRUCTIVE TESTING

Katholieke Universiteit Leuven

Belgium

µCT equipment at MTM

• Skyscan 1072

• 0-130 kV, 0-300 µA, microfocal spot size 10 µm (10 Watt) / 30-40 µm (40 Watt)

• X-Ray detector Cooled CCD-sensor 1024 x 1024 pixels, 10 bit dynamic range

• Object manipulator 400 mm linear movement

• 20 mm lifting, 2 µm step size, 360° rotation, 0.45° step size

• AEA Tomohawk on the Philips HOMX 161

• X-Ray source (Philips HOMX 161)

• Focal spot 5 to 200 µm

• Voltage range 5 - 160 kV, current up to 3,2 mA as low as 0,03 mA

• Distance source-object 15 mm to 920 mm, distance source-image intensifier 520-1500 mm

• Image intensifier TH 9428HX with field of view 220 mm / 170 mm / 115 mm

• X-Ray detector CCD-sensor 1024 x 1024 pixels, 10 bit dynamic range ADIMEC MX12P

• Object manipulators HOMX 161 X-Ray detector movement, object X, Y and Z movement

• Servostep 1700 Object rotation 0.01° step size and object X movement 1 µm stepsize

Achievements

• Filters in front of X-ray source or in front of detector• Dual energy procedures• Image enhancement programmes (denoising, missing

lines, …)• Programmes for quantitative data deduction from µCT

images

• See more in presentations of today…..

Data acquisition

• Images are converted to binary images using a simple threshold value

Image analysis

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CT-Image (grey-scale) Binary voxel representation

Graph of the pore network with k’s assigned

Geometry / Image processing

Fluid viscosity introduced arbitrarily

Overall conductivity

Geometrical parameter

Pore map

Graph of the pore network

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Outlet

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Skeleton

• Based on voronoï diagram;• Gives information about local sizes in the pore space;

Segmentation

• Place maximum balls in the pore space• Make them grow as balloon in tubes

Vectorization

• Each pore is represented by its center with its– Volume– Aperture– Connectivity with its neighbors

Pore network representation

• A local hydraulic conductivity is associated to each pore using Poiseuille law, depending on the sizes of pores

• Two sets of pore are selected for input and output.

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Results

Computed and measured permeability, 10-10 m2

  measured computed

Along warp, K1 1.790.40 1.52

Along weft, K2 1.430.30 1.06

Ratio K1/K2 1.25 1.43

Through the thickness - 0.0065

Glass laminate7*6*2.2 cm350*300*110 voxel (pixel size: 20 m)