IN-SITU ESEM STUDY ON WOOD CELLS UNDER TENSION

摘要

Environmental Scanning Electron Microscopy (ESEM) is a powerful tool in biomaterials science to observe biological samples in wet and therewith almost native condition. Samples can be examined at high magnifications with a large focal depth and little sample preparation minimizes possible artefacts. A specially designed tensile testing stage combined with a cooling device was used to examine single wood cells while straining. In order to gather information on the deformation and fracture behaviour at the cell and cell wall level unmodified early-, transition-, and latewood cells of a tree ring of Norway spruce (Picea abies [L.] Karst.) were studied. The in-situ micromechanical tensile tests revealed differences between the particular tissue types regarding the deformation patterns and crack propagation.