Sales & Marketing Alignment: How to Synergize for Success
Session 2 ic2011 belleville
1. Production and properties of sustainable wood-
welded panels from North American species
Benoît Belleville, Ulaval
Tatjana Stevanovic, Ulaval
Antonio Pizzi, ENSTIB
Alain Cloutier, Ulaval
June 19 2011
2. Plan of presentation
• Introduction and problematic
• Bibliographical review
• Objectives of research
• Results and discussion
• Conclusions and perspectives
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3. Introduction
• Rotational wood-dowel welding has been
shown to rapidly produce wood joints of
considerable strength without any adhesive.
• Mechanical properties similar to PVA
adhesive.
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4. Wood-dowel welding: How ?
• Mechanical friction at the interface;
• Temperature-induced softening and
degradation of polymer material;
• Composite formation: fibers/molten wood
material matrix.
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7. Wood-dowel welding: The interest ?
• Interesting and sustainable alternative for
paneling applications
• Green technology (only wood)
• Opportunity to increase productivity and
reduce costs in the furniture industry
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8. Problematic
• Evaluate the suitability of two North American
hardwood species, sugar maple (Acer
saccharum) and yellow birch (Betula
alleghaniensis) for the design of panels using
wood-dowel welding technology.
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9. Specific objectives
• Produce wood welded panels
• Evaluate mechanical properties under
constant and varying hygrometric conditions
• Compare with its PVA-glued counterpart
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10. Material and Methods: Paneling
• Wood-dowel welding performed with a
machine designed for paneling purposes.
• 12 panels produced for each species
• 6 PVA-glued panels produced for each
species in parallel for comparative purposes
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11. Material and Methods: Paneling
• 25x30x225 mm wood slats (12 per panel)
• Insertion along the edge and through
neighbouring slat (~50 mm)
• Dowels configuration
• 2.5 cm spacing between dowels and from edges
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13. Material and Methods: Welding parameters
• Commercial smooth wood dowels (Ф 9.67 mm)
in pre-drilled hole (Φ 7,67 mm)
• Optimized wood-dowel welding parameters for
individually studied species
• Sugar maple : 1000 RPM, 25.0 mm s-1
• Yellow birch : 1000 RPM, 16.7 mm s-1
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14. Material and Methods
• Panels tested following a typical protocol for
wood composite panels
• Three-point bending test
• Delamination following multiple cycles at
different hygrometric conditions
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15. Material and Methods: Three-point bending test
MTS QT 5 KN universal testing machine
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16. Material and Methods: Three-point bending test
• Load concentrated at center
• Dowels not continuous
throughout the panel (50 mm)
Fmax L
max 2 [1]
D 3
• Estimated load at break (σmax)
Yellow birch: 1502 N
Sugar maple: 1630 N
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18. Results and discussion: Bending
• 2 types of failure: Centre of
the panel or next to it.
• Fracture always in the dowels
• No slippage along weldline
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19. Results and discussion: Bending
Table 1. Average bending strength results
Species Type of Fmax ±SE1 Estimated Fmax
laminated joint (eq.1)
N N
Welded 1696.4 (136.2) 1630
Sugar maple
Glued 5746.1 (764.9) -
Welded 1790.2 (38.4) 1502
Yellow birch
Glued 5212.7 (521.9) -
1Standard error
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20. Results and discussion: Delamination
• No deformation observed in panels submitted
to conditioning cycles.
• Delamination observed in both types only
under dry conditions although not affecting
bending properties.
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21. Small-scale crib
100% sugar maple
No adhesive
66 cm wide (26’’)
46 cm high (18’’)
36 cm deep (14¼’’)
228 wood dowels
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22. Conclusions and perspectives
• Welded bond joint is not the weakest link
affecting panel mechanical properties.
• Wood-dowel welding is suitable for paneling
of North American species.
• Additional work required to improve the
automated assembling technique and panel
stability.
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