The limited elongation potential restricts the plastic deformation of paper and its products. An extension of this limit would be necessary to substitute materials like plastics in several branches for example the packaging industry. A compression of paper materials prior to forming is one possibility to influence the material behavior. This was already mentioned in recent literature. In the article at hand, the influence of compression pressures on the mechanical behavior and the micromechanical structure of a fresh fiber board were investigated. For this material it turned out that the lowest of three contact normal pressure levels was able to increase the strength as well as the extensibility of the specimens. Beyond this pressure level the maximum strain decreased in both directions of the material. Furthermore, the strength decreased in MD. These phenomena were substantiated with microscopic analyses of the fiber network. It is assumed that high compression levels led to longitudinal cracks of the fiber walls. The findings can be used to design the processes of hydro-based deep-drawing processes with counter pressure.
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