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An algorithm on geometrical data extraction, material reconstruction and numerical analysis is presented in order to reconstruct the actual wood-like cellular materials and investigate their linear elastic material behaviour in the transverse plane under different loading conditions. The algorithm implemented by Mathematica technical computing software is used to read the pixel data of cellular material images with a wide range of material scales, e.g. from micro-to millimeter scale. As a result of this process, geometrical properties including cell wall thicknesses, cell connectivities, vertex and center coordinates are determined. Identified geometrical properties are transferred to Abaqus/CAE computer aided engineering software by using a Python script and also

Nanoindentation (nanometer scale, extremely small) and impact (microsecond scale, extremely fast) experiments are two important techniques for characterizing modern material systems. However, these two experiments were often studied individually. In this pilot study, a multiscale indentation mechanics approach is proposed to correlate these two very different mechanics events acting on the same target materials using a spherical indenter and a projectile. The contact stiffness of nanoindentation of a target material is fitted using Hertz’s contact law, and then the contact stiffness of impact is obtained using a simplified multiscale relation. Therefore, the maximum impact force of a projectile impact can be predicted by inputting the impact energy and the contact stiffness of impact. The above new approach was validated by drop-weight impact experiments of polymers and structural composite materials subjected to low-energy impact. Results show that only a few minutes are needed to predict the maximum impact force.