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The aim of this work was to analyze the influence of fibers on the mechanical behavior of fiber-reinforced elastomers under cyclic loading. Thus, the focus was on the characterization of structure–property interactions, in particular the dynamic mechanical and viscoelastic behavior. Endless twill-woven glass fibers were chosen as the reinforcement, along with silicone as the matrix material. For the characterization of the flexible composites, a novel testing device was developed. Apart from the conventional dynamic mechanical analysis, in which the effect of the fiber orientation was also considered, modified step cycle tests were conducted under tensile loading. The material viscoelastic behavior was studied, evaluating both the stress relaxation response and the capability of the material to dissipate energy under straining. The effects of the displacement rate of the strain level, the amplitude of the strain applied in the loading–unloading step cycle test, and the number of the applied cycles were evaluated. The results revealed that an optimized fiber orientation leads to 30-fold enhanced stiffness, along with 10 times higher bearable stress. The findings demonstrated that tailored reinforced elastomers with endless fibers have a strong influence on the mechanical performance, affecting the structural properties significantly.

The focus of this paper is the realization and verification of a modified fiber bundle pull-out test setup to estimate the adhesion properties between threads and elastic matrix materials with a more realistic failure mode than single fiber debond techniques. This testing device including a modified specimen holder provides the basis for an adequate estimation of the interlaminar adhesion of fiber bundles including the opportunity of a faster, easier, and more economic handling compared to single fiber tests. The verification was done with the single-fiber and microbond test. Overall, the modified test setup showed the typical pull-out behavior, and the relative comparability between different test scales is given.

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This paper is dealing with the influence of processing parameters for manufacturing of steel-carbon-fiber-reinforced-plastic (CFRP) hybrid plates by using the one-shot-hybrid resin-transfer-moulding (OSH-RTM) process. A design of experiments study was carried out. The quality of the manufactured parts was quantified by the bending modulus, the apparent interlaminar shear strength (ILSS), the maximum deflection and the density of the CFRP. The following changeable processing parameters were chosen: mould temperature, resin temperature, change in mass flow and maximum injection pressure. It is shown that the mould temperature and the change in mass flow show significant impact on the flexural modulus, density and maximum deflection of the plate while there is no significant impact on the apparent ILSS. Furthermore, the interaction between the mould temperature and resin temperature is having an influence on the flexural modulus and density.