Elasto-viscoplasticity Behaviour of a Structural Adhesive Under Compression Loadings at Low, Moderate and High Strain Rates

International audience; Crashworthiness performance of automotives by introducing new materials is of high interest based on the global mass’ reduction of cars. Bonded techniques are tested at present with respect to the reduction of the mass/energy’s ratio combined with recycling processes. In this study, a compression test program is performed on a bulk structural adhesive under a very large range of strain rates, thus [0.1; 5000]/s. Uniaxial compression tests at 0.1 and 50/s are achieved using a high-speed hydraulic testing machine. A split Hopkinson bar’ device made of PA66 is experimented so as to characterize soft materials in the upper domain of strain rates, thus [500; 5000]/s. A special mold is used for the preparation of the adhesive plates. Two sheets are prepared (thickness 4 mm with 1 MPa pressure and 6 mm with 4 MPa pressure) in order to consider the effect of the pressure during the curing process. Water jet technique is used to extract cylindrical samples from the plates with accurate dimensions. The identification of the compression behaviour of the structural adhesive is lead with objective to find material parameters of a modified G’sell model for finite element modeling of crashworthiness.