Abstract
A research group on forest products from School of Agriculture – Sao Paulo State University. Brazil developed a portable hardness tester for wood, which is based on a displacement transducer and an embedded electronic processor for dynamic evaluation of hardness. This paper presents the results of calibration tests of the equipment, carried out on seven species of Eucalyptus. A new methodology for dynamic hardness calculation has been introduced, which relays on the reaction force of the indentation, while the measurements of indentation depth are performed under load. A moderate to strong linear correlation to Janka hardness and its variations were found. This new approach avoids the classical problems of Brinell hardness test in terms of “sinking-in” (causing diffuse edges) and elastic recovery of the indentation.
Acknowledgements
The authors express their gratitude for the financial support given by FAPESP – Sao Paulo Research Foundation for the development of this project (08/08414-0).
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©2017 Walter de Gruyter GmbH, Berlin/Boston
Articles in the same Issue
- Frontmatter
- Preparation of highly mesoporous wood-derived activated carbon fiber and the mechanism of its porosity development
- The sorption of monovalent cations onto wood flour and holocelluloses of Norway spruce: molecular interactions during LiCl impregnation
- Dynamic hardness of wood – measurements with an automated portable hardness tester
- Static and dynamic tensile shear test of glued lap wooden joint with four different types of adhesives
- Nondestructive bending tests on Douglas-fir utility poles as a potential tool for pole sorting and for prediction of their behavior in service
- Verification of the elastic material characteristics of Norway spruce and European beech in the field of shear behaviour by means of digital image correlation (DIC) for finite element analysis (FEA)
- Characterizing spatial distribution of the adsorbed water in wood cell wall of Ginkgo biloba L. by μ-FTIR and confocal Raman spectroscopy
- A comprehensive mathematical model of heat and moisture transfer for wood convective drying
- Phylogenetic analysis of wood-inhabiting molds and assessment of soft-rot wood deterioration. Part 5. Genus Aureobasidium
- Creating extended antimicrobial property in paper by means of Ag and nanohybrids of montmorillonite (MMT)
Articles in the same Issue
- Frontmatter
- Preparation of highly mesoporous wood-derived activated carbon fiber and the mechanism of its porosity development
- The sorption of monovalent cations onto wood flour and holocelluloses of Norway spruce: molecular interactions during LiCl impregnation
- Dynamic hardness of wood – measurements with an automated portable hardness tester
- Static and dynamic tensile shear test of glued lap wooden joint with four different types of adhesives
- Nondestructive bending tests on Douglas-fir utility poles as a potential tool for pole sorting and for prediction of their behavior in service
- Verification of the elastic material characteristics of Norway spruce and European beech in the field of shear behaviour by means of digital image correlation (DIC) for finite element analysis (FEA)
- Characterizing spatial distribution of the adsorbed water in wood cell wall of Ginkgo biloba L. by μ-FTIR and confocal Raman spectroscopy
- A comprehensive mathematical model of heat and moisture transfer for wood convective drying
- Phylogenetic analysis of wood-inhabiting molds and assessment of soft-rot wood deterioration. Part 5. Genus Aureobasidium
- Creating extended antimicrobial property in paper by means of Ag and nanohybrids of montmorillonite (MMT)