Mechanical properties as a function of density in particle boards
(2015) In TFHF-5196 FHL820 20142Solid Mechanics
- Abstract
- With better understanding of the properties and mechanical behavior of wood fiber composites such as wood particle boards the final structure can be improved, both from a solid mechanical and cost effective perspective. Particle boards are widely used in today’s industry for consumer products and the mechanical properties for such materials and how it is effected by the mix of wood chips and glue and thus the density of the board is therefore to be evaluated. This work suggests approximations for the mechanical properties with the density as an input parameter based on experimental tests.
To describe the mechanical properties as a function of particle board density a density measure is performed. This is done by using a 3D tomograph X-ray... (More) - With better understanding of the properties and mechanical behavior of wood fiber composites such as wood particle boards the final structure can be improved, both from a solid mechanical and cost effective perspective. Particle boards are widely used in today’s industry for consumer products and the mechanical properties for such materials and how it is effected by the mix of wood chips and glue and thus the density of the board is therefore to be evaluated. This work suggests approximations for the mechanical properties with the density as an input parameter based on experimental tests.
To describe the mechanical properties as a function of particle board density a density measure is performed. This is done by using a 3D tomograph X-ray machine available at Lund University. A small specimen of the particle board is scanned and a greyscale variation through the thickness of the board is obtained. The greyscale density curve is then scaled to real density values using the average density from the outer dimensions and weight measures of the specimen. The density variation is then known and the measuring of mechanical properties is done in a conventional way in a tensile machine, loading it with shear, bending and tensile loads. During its deformation the specimen is analyzed by a Digital Image Correlation technology using a camera to take images during the deformation and then correlating each part of the surface area of the specimen to obtain a strain field. The experimental strain field is then matched to a strain field obtained from a FE-analysis. The correct mechanical property is found when the strain field and global force matches for the experimental and FE values.
A linear approximation has been taken for the variation of the mechanical properties as a function of density. This was done as it seems to match the FE-strains well to the experimental strains. Optimization of the mechanical property variation with density would be far more time consuming, and a linear approximation was done. Poisson’s ratio is presented as an average value for all densities in this study. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/5146783
- author
- Svensson, Gustav LU
- supervisor
- organization
- course
- FHL820 20142
- year
- 2015
- type
- H3 - Professional qualifications (4 Years - )
- subject
- keywords
- Particle board, material model, tensile testing, digital image correlation, 3D tomography
- publication/series
- TFHF-5196
- language
- English
- id
- 5146783
- date added to LUP
- 2015-07-03 11:00:50
- date last changed
- 2015-07-03 11:00:50
@misc{5146783, abstract = {{With better understanding of the properties and mechanical behavior of wood fiber composites such as wood particle boards the final structure can be improved, both from a solid mechanical and cost effective perspective. Particle boards are widely used in today’s industry for consumer products and the mechanical properties for such materials and how it is effected by the mix of wood chips and glue and thus the density of the board is therefore to be evaluated. This work suggests approximations for the mechanical properties with the density as an input parameter based on experimental tests. To describe the mechanical properties as a function of particle board density a density measure is performed. This is done by using a 3D tomograph X-ray machine available at Lund University. A small specimen of the particle board is scanned and a greyscale variation through the thickness of the board is obtained. The greyscale density curve is then scaled to real density values using the average density from the outer dimensions and weight measures of the specimen. The density variation is then known and the measuring of mechanical properties is done in a conventional way in a tensile machine, loading it with shear, bending and tensile loads. During its deformation the specimen is analyzed by a Digital Image Correlation technology using a camera to take images during the deformation and then correlating each part of the surface area of the specimen to obtain a strain field. The experimental strain field is then matched to a strain field obtained from a FE-analysis. The correct mechanical property is found when the strain field and global force matches for the experimental and FE values. A linear approximation has been taken for the variation of the mechanical properties as a function of density. This was done as it seems to match the FE-strains well to the experimental strains. Optimization of the mechanical property variation with density would be far more time consuming, and a linear approximation was done. Poisson’s ratio is presented as an average value for all densities in this study.}}, author = {{Svensson, Gustav}}, language = {{eng}}, note = {{Student Paper}}, series = {{TFHF-5196}}, title = {{Mechanical properties as a function of density in particle boards}}, year = {{2015}}, }