Wood compression in four-dimensional in situ tomography

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Journal Title
Journal ISSN
Volume Title
A1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä
Date
2022-07-21
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Language
en
Pages
6
1-6
Series
Physical Review Materials, Volume 6, issue 7
Abstract
Wood deformation, in particular when subject to compression, exhibits scale-free avalanche-like behavior as well as structure-dependent localization of deformation. We have taken three-dimensional (3D) x-ray tomographs during compression with constant stress rate loading. Using digital volume correlation, we obtain the local total strain during the experiment and compare it to the global strain and acoustic emission. The wood cells collapse layer by layer throughout the sample starting from the softest parts, i.e., the spring wood. As the damage progresses, more and more of the softwood layers throughout the sample collapse, which indicates damage spreading instead of localization. In 3D, one can see a fat-tailed local strain rate distribution, indicating that inside the softwood layers, the damage occurs in localized spots. The observed log-normal strain distribution is in agreement with this view of the development of independent local collapses or irreversible deformation events. A key feature in the mechanical behavior of wood is then in the complex interaction of localized deformation between or among the annual rings.
Description
| openaire: EC/H2020/857470/EU//NOMATEN Funding Information: Acknowledgments. We acknowledge the European Synchrotron Radiation Facility for the provision of synchrotron radiation facilities and we would like to thank Marco di Michiel for assistance in using beam line ID15A. We thank Simo Huotari and Heikki Suhonen for their help in the application and data analysis process. M.J.A. acknowledges support from the Academy of Finland (Center of Excellence program, Grants No. 278367 and No. 317464). M.J.A. and T.M. acknowledge funding from the European Union Horizon 2020 research and innovation programme under Grant Agreement No. 857470 and from European Regional Development Fund via the Foundation for Polish Science International Research Agenda PLUS programme Grant No. MAB PLUS/2018/8. T.M. also acknowledges funding from The Finnish Foundation for Technology Promotion. J.K. acknowledges the funding from the Academy of Finland (Grant No. 308235) and Business Finland (Grant No. 211715). The Aalto Science IT project is acknowledged for providing computational resources. Publisher Copyright: © 2022 American Physical Society.
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Citation
Mäkinen , T , Halonen , A , Koivisto , J & Alava , M J 2022 , ' Wood compression in four-dimensional in situ tomography ' , Physical Review Materials , vol. 6 , no. 7 , L070601 , pp. 1-6 . https://doi.org/10.1103/PhysRevMaterials.6.L070601