Imaging the mechanical properties of wood cell wall layers by atomic force modulation microscopy

TitleImaging the mechanical properties of wood cell wall layers by atomic force modulation microscopy
Publication TypeJournal Article
Year of Publication2003
AuthorsClair, B., Arinero R., Leveque G., Ramonda M., & Thibaut B.
JournalIAWA JOURNAL
Volume24
Pagination223-230
Keywordsatomic force microscopy, cell wall, elastic modulus, mechanical properties, Wood
Abstract

Atomic Force Microscopy in force modulation mode was used to study the elastic properties of the different fibre wall layers of the tension wood of holm oak and normal wood of boco. The method is based on the measurement of the resonance frequency of the microscope lever in contact with the sample. This frequency is related to the reduced Young modulus E{*} = E/(1-nu(2)) of the material, supposed to be isotropic. `Elastic' images of the cell are obtained simultaneously with the topographic images, which allows the observation of the mechanical properties of the cells at a nanometric scale. Layers G, S-1, S-2 and ML can clearly be distinguished. By comparison with known materials an estimation of the absolute modulus is given in the range 5-20 GPa, but should be considered with caution, because the inherent anisotropy of the materials has not been taken into account.