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Intense acoustic shock waves were applied to evaluate the mechanical strength of structural epoxy bonds between a TA6V4 titanium alloy and a 3D woven carbon/epoxy composite material. Two bond types with different mechanical strengths were obtained from two different adhesive reticulations, at 50% and 90% of conversion, resulting in longitudinal static strengths of 10 and 39 MPa and transverse strengths of 15 and 35 MPa, respectively. The GPa shock waves were generated using ns-scale intense laser pulses and reaction principles to a confined plasma expansion. Simulations taking into account the laser–matter interaction, plasma relaxation, and non-linear shock wave propagation were conducted to aid interpretation of the experiments. Good correlations were obtained between the experiments and the simulation and between different measurement methods of the mechanical strength (normalized tests vs laser-generated shock waves). Such results open the door toward certification of structural bonding. [ABSTRACT FROM AUTHOR]

• For the first time, Numerical simulations of all prpcesses in the same code occuring in Laser shock adhesion test. • Laser matter interaction in direct and confine regime with water. • Shock wave propagation and interface break. • Comparison with previous experiments and new performed on assemblies using Velocimetry interferometer for any reflector. • Open the way for the numerical optimisation ot the laser test. The recent development of LAser Shock Adhesion Test (LASAT) as quantitative Non-Destructive Testing (NDT) process for evaluation of structural bonded assemblies brings new challenges. Applicative assemblies composed of complex materials with poor transverse mechanical properties and highly resistant bonded joints require laser parameters optimization and a more accurate control on the whole process. The development of a numerical tool is then necessary to ensure laser parameters specification to evaluate the bond mechanical strength for a given assembly. In this document, the ability of ESTHER code for the description of laser-matter interaction on aluminum and ablation pressure prediction is exposed. The influence of the target initial reflectivity on ablation pressure is investigated. In this paper, validation of the code in both direct (1 - 500 GW / cm 2 ) and water-confined (0 , 2 - 7 GW / cm 2 ) irradiation regimes is achieved with comparison to suitable sets of experimental data. Experiments were led on two laser facilities: the transportable laser shock generator (GCLT) at the CEA/DAM/DIF and the Hephaïstos facility at the Processes and Engineering in Mechanics and Materials laboratory (PIMM lab). Numerical models developed in this work are compared to previous experimental data and to reference models. Ablation pressures defined by our predictive models can then be coupled to other codes which are able to describe 2D/3D shock propagation, in order to model the entire LASAT process on complex assemblies. Characterization of a 6061 Aluminum/ Epoxy/ 6061 Aluminum assembly is achieved using ESTHER, showing its ability to master the phenomena involved in the LASAT process. For the first time, results open the full numerical design of laser adhesion test with the same code. [ABSTRACT FROM AUTHOR]