Change search
Refine search result
1 - 17 of 17
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Torkaman, Javad
    et al.
    Department of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran.
    Mojgan, Vaziri
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Mohammadi Limaeia, Soleiman
    Department of Forestry, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran.
    Relationship between branch-scar parameters and knot features of oriental beech (Fagus orientalis Libsky)2018In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 13, no 2, p. 117-120Article in journal (Refereed)
    Abstract [en]

    The classification of roundwood is inextricably linked to the measurement of a particular single wood defect. The appearance, location, and number of defects are important in the quality evaluation of logs and sawn timber, and the most important defects are knots. The purpose of this study was to investigate the relationship between the appearance of branch scars and features of the related knot inside oriental beech logs, and to model the relationship between well-defined branch-scar and knot parameters. One hundred and fifty knots in 15 stems of oriental beech trees were studied. Image analysis software was used to measure the branch-scar and knot features. The results showed a significant positive correlation between the branch-scar parameter “moustache length” and the knot length. The ratio of branch-seal length to width was found to be a good estimator of the stem diameter at the time of knot occlusion and the amount of clear wood between the knot occlusion and the bark. The relationship obtained for the oriental beech stem radius at time of knot occlusion confirms relationship reported for European beech (Fagus sylvatica L.).

  • 2.
    Berg, Sven
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Ekevad, Mats
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Vaziri, Mojgan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Crack influence on load-bearing capacity of glued laminated timber using extended finite element modelling2015In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 10, no 4, p. 335-343Article in journal (Refereed)
    Abstract [en]

    Most of the cracks are caused by changes in temperature and relative humidity which lead to shrinkage and swelling of the wood and thereby induce stresses in the structure. How these cracks influence the strength of the wooden structure, especially the shear strength, is not well understood. However, it is reasonable to expect that cracks have an impact on the shear strength as they preferably run along the beams in the direction of grain and bond lines. The purpose of this study was to investigate the load-bearing capacity of cracked glulam beams and to find a model that could predict the failure load of the beams due to the cracks. Three-point bending tests were used on glulam beams of different sizes with pre-manufactured cracks. An orthotropic elastic model and extended finite element method was used to model the behaviour of the cracked beams and to estimate the load-bearing capacity. The conclusions were validated by numerical simulations of the mechanical behaviour of three-point bending of glulam beams with different crack locations. The crack initiation load was recorded as the failure load and compared to the experimental failure load. The results of the compaction simulations agree well with the experimental results

  • 3.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Plessis, Anton du
    University of Stellenbosch.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Berg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Nano X-ray tomography analysis of the cell-wall density of welded beech joints.2015In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 10, no 4, p. 368-372Article in journal (Refereed)
    Abstract [en]

    This paper reports the results of a novel approach using nano X-ray computed tomography (CT) for the non-invasive determination of the weld-line density profile of welded wood joints. As a case study, wood samples with a dimension of 2 mm × 2 mm × 20 mm were cut from a board of welded beech (Fagus sylvatica L.). The spatial resolution of the X-ray scan was 500 nm. Densitometry results showed that welding was accompanied by a considerable increase in the bulk density and a decrease in the cell-wall density at the weld-line. The cell-wall density in the weld-line was almost 33% less than that of the unaffected wood. As an additional application of nano computed tomography, the 3D imaging also revealed details of the internal structure of the welded sample. This study showed that nano-CT is a powerful tool for the descriptive and quantitative study of welded wood

  • 4.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Rogaume, Caroline
    ENSTIB-LERMAB, University of Lorraine.
    Masson, Eric
    ENSTIB-LERMAB, University of Lorraine.
    Pizzi, Antonio
    ENSTIB-LERMAB, University of Lorraine.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    VOC emissions from linear vibration2015In: Proceedings of the 1st COST Action FP1407 Conference: Life Cycle Assessment, EPDs and Modified Wood, Koper, Slovenia, August 25-26 / [ed] A. Kutnar; M. Burnard; M. Schwarzkopf ; A. Simmons, Koper, Slovenia: University of Primorska, Scence and Research Centre of Koper , 2015, p. 26-27Conference paper (Refereed)
  • 5.
    Sandberg, Dick (Editor)
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Vaziri, Mojgan (Editor)
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Final Cost Action FP0904 Conference: “Recent Advances in the Field of TH and THM Wood Treatment” : May 19-21, 2014, Skellefteå, Sweden : book of abstracts2014Report (Refereed)
  • 6.
    Sandberg, Dick
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Vaziri, Mojgan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Trischler, Johann
    Linnæus University, Forestry and Wood Technology.
    Öhman, Micael
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    The role of the wood mechanical industry in the Swedish forest industry cluster2014In: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 29, no 4, p. 352-359Article in journal (Refereed)
    Abstract [en]

    The forest and forest products form one of the most important basis for the transfer to a biobased economy in Sweden. About 75% of the area covered by forest in Sweden is used industrially to produce raw material for the wood-refining industries. Every year, this cluster uses 75 million m3 of roundwood and has an export value of € 12 billion. This review paper is devoted to the wood mechanical industry, i.e. the industry which turns the forest into sawn timber, packaging, construction wood, furniture and interior fittings. The sawmills consume about half of the volume of softwood which is felled, and about two thirds of the sawn timber goes to export without any further refining within the country. Nevertheless, in spite of the relatively low degree of refinement in the sawmill and the fact that the sawmills in general over time have a very low profitability, they are responsible for 70–80% of the forest owners' profits on the sale of timber. An increased upgrading of the sawn timber within the country is desirable from a national economic viewpoint – increased employment opportunities, increased export income etc. It should then in the first place be for products with a higher added value, such as furniture and fittings. Today, the refinement value is 15–20 times higher for products from joinery and furniture industries compared that of the sawn timber and the added value of the wood within the building industry is only about 1.5 times.

  • 7.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Berg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Three-dimensional finite element modelling of heat transfer for linear friction welding of Scots pine2014In: Final Cost Action FP0904 Conference: “Recent Advances in the Field of TH and THM Wood Treatment” : May 19-21, 2014, Skellefteå, Sweden : book of abstracts / [ed] Mojgan Vaziri; Dick Sandberg, Skellefteå: Luleå tekniska universitet, 2014, p. 45-46Conference paper (Refereed)
  • 8.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Berg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Gheinani, Iman Tavakoli
    Department of Mechanical Engineering, ENSTIB-LERMAB, University of Lorraine.
    Three-dimensional finite element modelling of heat transfer for linear friction welding of Scots pine2014In: Wood Material Science & Engineering, ISSN 1748-0272, E-ISSN 1748-0280, Vol. 9, no 2, p. 102-109Article in journal (Refereed)
    Abstract [en]

    Finite element numerical analyses were performed to determine three-dimensional heat flux generated by friction to wood pieces during linear friction welding. The objective was to develop a computational model to explain the thermal behaviour of welded wood material rather than experimental methods, which are usually expensive and time consuming. This model serves as a prediction tool for welding parameters, leading to optimal thermo-mechanical performance of welded joints. The energy produced by the friction welding of small wood specimens of Scots pine (Pinus sylvestris L.) was determined by thermocouples and used as input data in the model. The model is based on anisotropic elasticity and the thermal properties were modelled as isotropic. This numerical simulation gave information on the distribution of the temperature in the welding interface during the entire welding process. A good agreement between the simulation and experimental results showed the appropriateness of the model for planning welded wood manufacture and prediction of thermal behaviour of wood during other mechanically induced vibration processes. The specimens presented in this model required a heat flux of 11 kW/m2 to achieve a satisfactory welding joint

  • 9.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Berg, Sven
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Sandberg, Dick
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Gheinani, Iman Tavakoli
    ENSTIB-LERMAB, University of Lorraine.
    Wood modification through mechanically induced wood fusion welding: 3-D finite element modelling of heat transfer.2014In: The seventh European Conference on Wood Modification (ECWM7: Book of Abstracts / [ed] Lina Nunes; Dennis Jones; Callum Hill; Holger Militz, Lissabon, 2014, p. 43-44Conference paper (Refereed)
  • 10.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Lindgren, Owe
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Pizzi, Antonio
    ENSTIB-UHP, Epinal.
    Influence of machine setting and wood parameters on crack formation in Scots pine joints produced by linear friction welding2012In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 26, no 18-19, p. 2189-2197Article in journal (Refereed)
    Abstract [en]

    Previous investigations on linear welded woods have shown that the connections are not sufficiently resistant to water for use in outdoor conditions. Therefore, they are utilized mainly for non-structural use, with only short time exposure to varying humidity. Influences of some welding and wood parameters such as welding pressure, welding time and heartwood or sapwood on crack formation in the weldline of Scots pine (Pinus sylvestris) were investigated. Axial samples measuring 200 mm×20 mm×20 mm from Scots pine were welded, placed vertically in 5-mm-deep tap water and were taken out of the water one at a time after each 10 min of water absorption. Then they were scanned and put back into water until the first crack appeared in the weldline. An X-ray Computer Tomography (CT-) scanner was used to monitor water movement and density change in the weldlines during water absorption–desorption. CT-scanning enabled to detect the cracks as they formed in the weldline and could be used in wood welding studies. Data evaluation showed that all the three studied parameters had significant effects on crack formation and that crack occurrence could be postponed by using heartwood samples with 1.3 MPa welding pressure and 1.5 s welding time.

  • 11. Vaziri, Mojgan
    et al.
    Lindgren, Owe
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Pizzi, Antonio
    ENSTIB-UHP, Epinal.
    Optimization of tensile-shear strength for linear welded Scots pine2012In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 26, no 1-3, p. 109-119Article in journal (Refereed)
    Abstract [en]

    The mechanical performance of welded wood has a decisive role in its applications. This study was performed to determine the welding conditions that optimized the tensile-shear strength of welded Scots pine (Pinus sylvestris). Tensile-shear strength as a function of welding pressure, welding time and holding time1 was measured according to European standard EN 205. Maximum tensile-shear strength of welded sample was 9.3 MPa that was obtained using 1.3 MPa welding pressure, 2.8 s welding time and 70 s holding time. This tensile-shear strength was about two times that of PVAc-glued samples. According to data evaluation tensile-shear strength could be optimized to 9.7 MPa by increasing the welding time to 3.5 s and decreasing the holding time to 60 s.

  • 12.
    Mansouri, Hamid
    et al.
    ENSTIB-UHP, Epinal.
    Pizzi, Antonio
    ENSTIB-UHP, Epinal.
    Leban, Jean-Michel
    INRA, Campenoux.
    Delmotte, L.
    Lindgren, Owe
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Vaziri, Mojgan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Causes for the improved water resistance in pine wood linear welded joints2011In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 25, no 16, p. 1987-1995Article in journal (Refereed)
    Abstract [en]

    Linear vibration welding of good quality pine (Pinus sylvestris) wood from Sweden containing a small proportion of a native mixture of terpenoic acids, known under the collective name of rosin, has been shown to yield joints of much upgraded water resistance. This has been shown to be due to the protecting influence the molten rosin from the wood itself has on the welded interphase, because of the water repellency of rosin. Joints of unusually high percentage wood failure but modest strength were obtained, rosin apparently reinforcing the welded interphase to yield weldline strengths always much higher than the strength of the surrounding wood.

  • 13.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Lindgren, Owe
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Pizzi, Antonio
    ENSTIB-LERMAB, Université Henri Poincaré - Nancy.
    Influence of welding parameters and wood properties on the water absorption in Scots pine joints induced by linear welding2011In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 25, no 15, p. 1839-1847Article in journal (Refereed)
    Abstract [en]

    Wood welding is an environmentally-friendly and very quick technique to yield wood joints in just a few minutes and without using any adhesives. The only limitation of welded wood is that the joint is suitable only for interior use. Exterior use, or use in an environment with varying humidity requires water resistance of the welded joints. An investigation was performed to determine the effects of welding parameters and wood properties on water absorption in the weldline and how to reduce it through controlling the production parameters. The influences of welding pressure, welding time, and heartwood/sapwood on water absorption in the weldline of Scots pine (Pinus sylvestris) joints were investigated. Specimens composed of two pieces of heartwood or sapwood, each of dimensions 200 mm × 20 mm × 20 mm, were welded together to form specimens of dimensions 200 mm × 20 mm × 40 mm. The specimens were allowed to stand in 5-mm-deep tap water and then they were taken out of the water one at a time and scanned in 10-min intervals until the first crack appeared in the weldline. An X-ray Computerized Tomography scanner was employed to monitor water movement and density change in weldlines during water absorption-desorption. All three evaluated parameters showed significant effect on water absorption. Samples of heartwood welded by 1.3 MPa welding pressure and 1.5 s welding time showed the lowest water absorption

  • 14.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Lindgren, Owe
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Pizzi, Antonio
    ENSTIB-LERMAB, Université Henri Poincaré - Nancy.
    Influence of weldling parameters on weldline density and its relation to crack formation in welded Scots pine joints2011In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 25, no 15, p. 1819-1828Article in journal (Refereed)
    Abstract [en]

    Exterior use of welded wood laminates without further treatment is not recommended. Frictional welded joints have poor resistance to moisture variation, especially to drying. Therefore, application of welded woods is limited to interior use without exposure to highly variable air humidity. Influences of some welding and wood parameters such as welding pressure, welding time and heartwood/sapwood on weldline density of Scots pine (Pinus sylvestris) joints were investigated. Interdependence between density and water resistance of weldline (in terms of crack time) was also studied by comparing the results of this investigation with those of the earlier studies. Specimens composed of two wood pieces, each measuring 20 mm x 20 mm x 200 mm, were welded together to form a specimen measuring 40 mm x 20 mm x 200 mm by a vibration movement of one wood surface against another at a frequency of 150 Hz. An X-ray Computerized Tomography scanner was used to measure weldline density. Weldlines of sapwood produced by 1.3 MPa welding pressure and 1.5 s welding time showed the highest density. No correlation between weldline density and crack time was evident.

  • 15.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Orädd, Greger
    Department of Radiation Sciences, Umeå University.
    Lindgren, Owe
    Pizzi, Antonio
    ENSTIB-UHP, Epinal.
    Magnetic resonance imaging of water distribution in welded woods2011In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 25, no 16, p. 1997-2003Article in journal (Refereed)
    Abstract [en]

    This study was performed for a better understanding of water effect on welded wood and improving its water resistance. In this article, we have also attempted to demonstrate the feasibility of using Magnetic Resonance Imaging technology to study water movement in welded woods. Water distribution in welded woods of Scots pine (Pinus sylvestris) and beech (Fagus sylvatica) was investigated by Magnetic Resonance Imaging. Axial specimens were cut from beech and sapwood of Scots pine in longitudinal direction of wood grain. Two pieces of each wood species were welded together by a linear vibration machine. Sub-samples measuring 30 mm × 20 mm × 100 mm were cut from the welded specimens for Magnetic Resonance Imaging. The results showed that weldline of Scots pine was more resistant to water than weldline of beech. Pine joint was still holding after 40 h immersion in water, while a rapid wetting of the beech joint resulted in breakage of the joint in even less than an hour. This preliminary study also showed that MRI is a powerful tool to measure water distribution in welded woods and highlighted the potential of this technique to enhance understanding of wood welding

  • 16.
    Vaziri, Mojgan
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Water resistance of Scots pine joints produced by linear friction welding2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Wood welding is a mechanical friction process allowing the assembly of timber without any adhesives. The process consists of applying mechanical friction, under pressure, alternately to the two wood surfaces to be welded. This process can be applied to weld two flat pieces of timber, originating from the same or different tree species, and can be used in the manufacture of furniture and wood joinery. The only limitation is that the joint is not exterior-grade, but only suitable for interior joints. Exterior use, or use in an environment with varying humidity demands water resistance of the welded joints. The main objective of this thesis is to study the water resistance of the welded wood. This is complemented with special attention to non-destructive test methods such as X-ray Computed Tomography (CT-) scanning and Magnetic Resolution Imaging (MRI). The influence of welding parameters and wood properties on crack formation and crack propagation in the weldline was investigated. The influence of these parameters on weldline density and water absorption in the weldline were also studied. Investigations in this thesis are based on welded samples of Scots pine (Pinus sylvestris) of the dimensions 200 mm × 20 mm × 40 mm which were cut in the longitudinal direction of the wood grain. The tensile-shear strength of the welded Scots pine samples were determined using European standard EN 205. Different non-destructive methods such as X-ray Computed Tomography (CT-) scanning to study crack formation and propagation, and magnetic Resolution Imaging (MRI) to characterize water penetration and the distribution mechanism in welded wood were used. Solid state CPMAS 13C NMR spectrometry and X-ray microdensitometry investigations were carried out to study the mechanism of adhesion in Scots pine. These various non-destructive methods offer the advantage of non-invasive analysis and the elimination of any artifacts present due to preparation and sectioning. The most important results are summarized as follows: •X-ray Computed Tomography (CT-) scanning and Magnetic Resolution Imaging (MRI) are versatile research methods applicable to investigations of welded woods. •Water resistance of welded Scots pine can be increased using heartwood, a welding pressure of 1.3 MPa, and a welding time of 1.5 s. •Optimization tests showed that the tensile-shear strength of Scots pine was more sensitive to welding time changes than holding time and could be optimized to more than 9.7 MPa using 1.3 MPa welding pressure, > 3.5 s welding time, and < 60 s holding time. •Changing welding parameters and wood properties can increase water resistance of welded wood to some extent, but treating the weldline with certain natural and environmentally-friendly water repellents is still necessary. •Welded Scots pine shows unusually high water resistance and tensile-shear strength. This may be explained by there being more extractives compounds in Scots pine. •MRI experiments showed that the origin of the joint failure in welded beech is poor water resistance of the weldline, while swelling and shrinkage of wood are the main reasons for joint failure of welded Scots pine. •Extractives in Scots pine dramatically improve water resistance of the welded joint, but not to a level to classify the joint as an unprotected exterior grade. However, it can qualify as a joint for protected semi-exterior application.

  • 17.
    Vaziri, Mojgan
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Lindgren, Owe
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Pizzi, A.
    ENSTIB-LERMAB, Université Henri Poincaré - Nancy.
    Mansouri, H.R.
    ENSTIB-LERMAB, Université Henri Poincaré - Nancy.
    Moisture sensitivity of Scots pine joints produced by linear frictional welding2010In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 24, no 8, p. 1515-1527Article in journal (Refereed)
    Abstract [en]

    The industrial application range of welded wood so far has been limited to interior use because of its poor moisture resistance. Influences of some welding and wood parameters such as welding pressure, welding time, and heartwood/sapwood on water resistance of Scots pine (Pinus sylvestris) were investigated. An X-ray Computed Tomography scanner was used to monitor density change in weldlines during water absorption-desorption. Axial samples measuring 200 mm × 20 mm × 20 mm from Scots pine were welded and placed standing in 5-mm-deep tap water. Then they were taken out of the water one at a time and scanned at 10-min intervals until the first crack appeared in the weldline where the two parts of each specimen made connection. Results showed that the X-ray Computed Tomography can be used as an effective tool to study welded wood. Welding pressure, welding time, and heartwood/sapwood showed significant effect on length and location of the crack in the welded zone. Data evaluation showed that combination of 1.3 MPa welding pressure, 1.5 s welding time and using heartwood led to highest moisture resistance, which produced only a very short crack in the beginning of the weldline

1 - 17 of 17
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf