Experimental study of aluminium honeycomb behaviour under dynamic multiaxial loading
1 National Engineering School of Sfax, U2MP, BP. W3038, Sfax, Tunisia
2 University of Valenciennes and Hainaut-Cambresis. LAMIH, UMR 8201-CNRS, 59313 Valenciennes, France
Split Hopkinson Pressure Bar system (SHPB) with large-diameter and Nylon bars introducing a shear-compression loading device is used in order to investigate the dynamic behaviour of aluminium honeycomb under multiaxial loadings conditions. All shear-compression configurations including the loading angle variation from 0∘ to 60∘ are performed with an impact velocity of about 15m/s. The adapted SHPB system with the device are validated numerically and a phenomenon of separation between the input bar and the input beveled bar is observed. Numerical results suggest that this phenomenon provides a cutting of the reflected wave. An electro optical extensometer is employed in experiments. A good agreement between the numerical elastic waves and the experimental ones is obtained. Experimental results show a significant effect of the loading angle on the apparent stress-strain curves. The initial peak value and the plateau stress decrease with the increase of the loading angle. The combined shear-compression device with an enhancement at the alignment set-up provides efficient results for samples dynamically loaded. This device will be used to investigate the influence of the in-plane orientation angle on the deformation mechanisms and multiaxial behaviour of aluminium honeycomb under dynamic and quasi-static loading conditions.
© Owned by the authors, published by EDP Sciences, 2012