Cover page describe the Typical fracture surface of nuclear graphite blocks after irradiation (cracks occur during reactor operation). This picture Summarize the Fractographic studies of GR-280 nuclear graphite after irradiation up to neutron fluence above the turnaround dose (with a decrease in of the mechanical properties to the values close to the initial one after primary radiation-induced increase) showed along with the presence of transcrystalline fracture, appearance of intercrystalline fracture regions along the “filler-binder” type boundaries.
Staking lay-up effect on dynamic compression behaviour of e-glass/epoxy composite materials: experimental and numerical investigation
Mostapha Tarfaoui1, 2*, Mourad Nachtane1, 3
1ENSTA Bretagne, IRDL - UMR CNRS 6027, F-29200 Brest, France
2University of Dayton, Nanomaterials Laboratory, Dayton, OH 45469-0168, United States
3Laboratory for Renewable Energy and Dynamic Systems, FSAC - UH2C, Morocco
Adv. Mater. Lett., 2018, 9 (11), pp 816-822
Publication Date (Web): Jul 25, 2018
Copyright © 2018 VBRI Press
Several industrial applications have exposed polymer matrix composite materials to a very high strain rate loading conditions, requiring an ability to understand and predict the material behaviour under these extreme conditions. Many composite aircraft structures such as fuselage, wing skins, engine nacelles and fan blades are situated such that impacts at high strain rates are a realistic threat. To investigate this threat, high velocity impact experiments and subsequent numerical analysis were performed in order to study the compressive loading of composite materials at high strain rates. Specimens are subjected with various orientations from low to high strain rates to determine the compressive material properties. Three fibre orientations such as: ±20°, ±60° and 90° of cubic geometry are tested in in-plane direction. The tests show a strong material sensitivity to dynamic loading and fibre direction. In the second part, the FEA results of the dynamic tests resulting in no damage appeared satisfactory. The FEA gives results which are in coherence with the experimental data. The improved understanding of these phenomena and the development of predictive tools is part of an ongoing effort to improve the long-term integrity of composite structures under dynamic loads.
Composites, dynamic compression, experimental approach, finite element modelling.