Fracture zone Characterization—Micro-Mechanical Study
Keywords:Fracture mechanics, fracture zone, <i>in-situ</i> real-time SEM observations, crack profiles, fiber bridging, toughening
AbstractThe experimental and numerical characterization of the fracture process zone in softwoods is presented. In-situ real-time Scanning Electron Microscopy (SEM) was used as a tool to examine the physical mechanism of fracture in softwoods (spruce) using end-tapered Double Cantilever Beam specimens. Fracture process zone has been characterized in terms of failure mechanisms. It was found that bridging behind the crack tip is the main toughening mechanism, which contributes to nonlinear wood behavior in the presence of stress concentrations.
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