Fatigue strength of S-Ply® leaf springs

  S-Ply® is a glass-fibre composite material that is suitable for the highest dynamic requirements. The load carrying and supporting material is a strictly parallel-orientated, non-woven, glass- or carbon-fibre laminate (UD-prepregnated).     The glass-fibres are not stretched and not bent. In contrast to metallic materials with an isotropic structure, they are direction dependent and therefore can be aligned to suit the material structure. Epoxy resin compounds are used as binding agents. Their special balanced composition ensures high adhesive to the glass fibre surface, resulting in optimum dynamic and electrical properties. The ratio of matrix resin and reinforcement fibres has been chosen to profit from all the benefits offered by the raw materials selected to form the composite material.  The matrix fulfils a number of important tasks. It provides fixing for the fibre in the desired arrangement and supports it against buckling when under compressive stress. In addition, it has g