3D Microstructure Characterization of Wood Based PanelsWood Based Panels

Gernot STANDFEST1, Simon KRANZER2, Dietmar SALABERGER3, Bernhard PLANK3, Alexander PETUTSCHNIGG1, Manfred DUNKY4

1Salzburg University of Applied Sciences, Markt 136a, A-5431 Kuchl, AUSTRIA 2Salzburg University of Applied Sciences, Urstein Süd1, A-5412 Puch, AUSTRIA

3U A t i U i it f A li d S i St l h t 23 A 4600 W l AUSTRIA33Upper Austrian University of Applied Sciences, Stelzhammerstrasse 23, A-4600 Wels, AUSTRIA3

4Kronospan GmbH Lampertswalde, Mühlbacherstrasse 1, D-01564 Lampertswalde/Dresden, GERMANYgernot.standfest@fh-salzburg.ac.at

Contents of Presentation

1 Introduction1. Introduction2. Materials and Methods3. Results4 Summary4. Summary5. Future Tasks

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1 Outline

• Use of sub-µm-computed tomography for theUse of sub µm computed tomography for the characterization of wood based panels

• Determination of sample sizes for individual wood-• Determination of sample sizes for individual wood-based materials

• Qualitative assessment of CT data• Qualitative assessment of CT data• Quantitative analysis to analyze the pore size

di t ib ti f d b d ldistribution of wood based panels• Investigation of a relationship between pore structure

d tiand properties

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2.1 Materials

• OSB• OSB• Particleboard• MDF

– Stored under standard climate conditions– Measurment of density profileMeasurment of density profile– Vacuum packing for transportation

purposes

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2.2 Computed Tomographyp g p y

phoenix|x ray Nanotom 180phoenix|x-ray Nanotom 180Cone beamCone beam

DetectorX-ray source Sample

Detector

1500 projectionsVoltage between 60 kV and 85 kVMeasurement time between100 und 230 minutes/scan

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minutes/scan

2.3 Image Analysisg y

• Determination of Region of• Determination of Region ofInterest (ROI)

• Filtering for noisereductionreduction

• Histogram based thresholdy

x

stog a based t es o ddepending on panel type

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2.3 Image Analysisg y

Mathematical MorphologyMathematical Morphology

ErosionDilationOpeningOpening

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2.3 Image Analysisg y

Principle of OpeningPrinciple of OpeningDilatationErosion

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2.3 Image Analysisg y

Pore size distributionPore size distributionwith a family ofgrowing structuringgrowing structuringelements

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3 Qualitative Results

Panel Sample size [mm³] Achieved Resolution [µm/voxel edgePanel Sample size [mm ] Achieved Resolution [µm/voxel edgelength]

OSB 50 x50x18 31.1PB 30x30x19 17.0MDF 4x4x19 3.2

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3 OSB

Mean pore size: 424 µm

0,14

Mean pore size: 424 µmΓ-distributed

0 10

0,12

0,08

0,10

uenc

y

40332 mm³

0,04

0,06

Freq 10485 mm³

2628 mm³657 mm³

0 00

0,02657 mm³

0,000 1000 2000 3000 4000

Pore Size [µm]

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3 PB

Mean pore size: 252 µm

0,12

Mean pore size: 252 µmΓ-distributed

0,10

0,06

0,08

uenc

y

26229 mm³

0,04

,

Freq 19609 mm³

2496 mm³314 mm³

0 00

0,02314 mm³

0,000 500 1000 1500 2000

Pore Size [µm]

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3 MDF

Mean pore size: 27 µm

0,30

Mean pore size: 27 µmΓ-distributed

0,25

0,15

0,20

uenc

y

38.4 mm³

0,10

0,15

Freq

u

9.6 mm³2.4 mm³0 6 mm³

0 00

0,050.6 mm³

0,000 50 100 150 200 250

Pore Size [µm]

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3 MDF

Pore size as a functionPore size as a functionof density

4045

35

40

ted

m]

m]

y = 0,0441x - 6,0765R² 0 9532 25

3035

30

35

conn

ect

eria

l [µm

Size

[µm

R² = 0,9532

152025

25

size

of c

wal

l mat

e

n Po

re S

Pores

y = -0,0339x + 52,047R² = 0 6566

51020

Mea

n s

cell

w

Mea

n Pores

Cell wall material R² = 0,6566 015

600 700 800 900 1000Density [kg/m³]

material

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4 Summaryy

• Sub µm CT for the characterisation of• Sub-µm-CT for the characterisation ofwood based panels

• Determining the sample sizes for individual wood based materialsindividual wood-based materials

• Qualitative assessment of CT dataQua tat e assess e t o C data• Quantitative analysis of the pore

structure of wood based panels

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5 Future Tasks

• Evaluation of fiber and particle• Evaluation of fiber and particleorientation

• Evaluation of mechanical propertiesrelated to microstructurerelated to microstructure

• In-situ investigation of swelling and/ors tu est gat o o s e g a d/oshrinkage

• CT based modeling of wood basedpanelspanels

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Acknowledgementsg

The authors would like to acknowledgeThe authors would like to acknowledge financial support from the Austrian Research Promotion Agency (FFG) within the FHplus In Coin programmewithin the FHplus In Coin programme(Project number 198353).

Thank you for your attention!Thank you for your attention!

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