TY - GEN A1 - Müller, Alexander A1 - Trappe, Volker A1 - Hickmann, Stefan A1 - Ortwein, H.-P ED - Christ, Hans-Jürgen T1 - Investigation of the infinite life of fibre-reinforced plastics using X-ray refraction topography for the in-situ, nondestructive evaluation of micro-structural degradation processes during cyclic fatigue loading N2 - The described investigation of carbon-fibre-reinforced plastics (CFRP) documents that damage evolution can be observed by means of X-ray refractography. Comparative investigations with synchrotron technique on CFRP and grey-scale analysis on glass fibre-reinforced-plastics (GFRP) confirm these results. Moreover it was found that the fracture mechanical properties of the matrix system influence damage nucleation and propagation in the laminate during static and fatigue loads. Single-step fatigue tests were carried out on Laminates with RIM135 and LY556 matrix systems made from non-crimped fabric (NCF) or twill weave in different fibre orientations. The damage to the LY556 laminates was characterized by laminate cracks growing rapidly over the whole specimen width, whereas the damage on the RIM135 laminates was characterized by an earlier onset of micro-cracking followed by laminate cracks. The specimens were fatigued up to 108 (very high cycle fatigue (VHCF) regime) load cycles. S-N-curves of damage initiation were drawn and boundaries were identified for endurance within the VHCF regime. A phenomenology based model focusing on matrix stress was applied to reproduce the first inter-fibre failure (IFF) under static and fatigue loads. KW - Carbon fibre-reinforced-plastics KW - Fatigue KW - Damage evolution KW - X-ray refractography KW - Very high cycle fatigue PY - 2018 SN - 978-3-658-24531-3 U6 - https://doi.org/10.1007/978-3-658-24531-3 VL - 2018 SP - 417 EP - 439 PB - Springer Spektrum CY - Wiesbaden ET - 1. Auflage AN - OPUS4-50096 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -