Détermination expérimentale du comportement mécanique et de critère de rupture d'assemblages sous chargements mixtes. Application aux rivets et points soudés

The paper deals with a new experimental procedure for joint characterisation. New experimental set-ups are based on the Arcan protocol which was first developed for composite delamination studies. This specific test enables one to mix and control the distribution of tensile and shear loads in the specimen. In the first part of the paper, a specific set-up is developed and the Arcan procedure is used and applied for riveted joints. The non-linear behaviour and a failure criterion are defined and identified. In the second part, this procedure is used and applied to spotwelds. For this kind of joints, the main problem is to attach the specimen to the set-up properly (without stamping or bending the metal plates of the specimen). The solution is based on the use of the soldering joint. However, it was first necessary to measure the influence of the melting temperature of the silver/tin alloy regarding the material properties, the strength and the microhardness of the spotweld. Arcan test procedure is then applied to spotwelds. Finally, results prove the ability of this new experimental protocol to define non-linear behaviour of rivets and spotwelds until failure. The interest of these experiments is also to evaluate and eventually improve the representativeness of equivalent joint models used for structural analysis in terms of behaviour and failure criterion.