Figures & data
Figure 1. P. abies microstructure: (a) optical image of the bulk wood sample; (b) microstructure of wood; (c) single hollow wood cell; (d) environmental scanning electron micrograph of the interface between late (bottom) and early wood (top) regions (scale bar is 40 μm); (e) topographical image of late wood cells obtained by the imaging mode of the nanoindenter, image size is 50 × 50 μm2; (f) schematic representation of a single cell and its comprising layers.
Figure 2. (colour online) A schematic representation of the experimental set-up.
Figure 3. Mechanical properties of the secondary wood cell wall, S2, in P. abies: (a) the average hardness and reduced modulus measured in a static nanoindentation mode: at four RHs of 6, 31, 50 and 79% – circles, water submerged specimen representing 100% RH – diamonds, at 60% RH – rectangles (adapted from Ref. [Citation33]) and reduced moduli collected from literature measured in a “dry” state – pink circle (adapted from Ref. [Citation18]); (b) representative load-displacement curves measured in four corresponding RHs of 6, 31, 50 and 79%; (c) representative reference contact depth-time curves measured in a dynamic nanoindentation mode at two RHs of 6 and 79%; the insert is a schematic description of the dynamic nanoindentation measurement mode. © Hysitron Inc.
![Figure 3. Mechanical properties of the secondary wood cell wall, S2, in P. abies: (a) the average hardness and reduced modulus measured in a static nanoindentation mode: at four RHs of 6, 31, 50 and 79% – circles, water submerged specimen representing 100% RH – diamonds, at 60% RH – rectangles (adapted from Ref. [Citation33]) and reduced moduli collected from literature measured in a “dry” state – pink circle (adapted from Ref. [Citation18]); (b) representative load-displacement curves measured in four corresponding RHs of 6, 31, 50 and 79%; (c) representative reference contact depth-time curves measured in a dynamic nanoindentation mode at two RHs of 6 and 79%; the insert is a schematic description of the dynamic nanoindentation measurement mode. © Hysitron Inc.](/cms/asset/79e3dcaa-302a-4b56-a4cb-992bad92284c/tphm_a_920544_f0003_oc.gif)