ASAP

When a road accident happens, the structure of the vehicle is designed to absorb a part of the energy released by the shock, the objective being to protect as much as possible the occupants of the vehicle. The quality of the assembly, and more particularly the spot weldings, is a key stake to ensure the absorption of the energy by deformation of the parts and rupture of fusible points. However, the irregular geometry of the profile and the bad quality of the surface of the spot weldings make particularly difficult the application of inspection methods. Moreover, the automotive industry is subject to a high competitiveness, which in the context of respect of the environment, results in technological breakthroughs as for example the structure lightening of the vehicle and the development of the electric vehicles. These new stakes must be realized by maintaining a high level of safety of the vehicles. ASAP will answer these challenges context by developing a new methodology in non destructive testing allowing an optimized monitoring of the assemblies. The objectives of ASAP will be to study and develop a new phase-array ultrasonic method. One of the innovations of the project will be to implement within this instrumentation dedicated algorithms allowing to adapt in real-time to the complex geometry of the spot welding, to improve the performances of detection, and to have an automatic interpretation of the quality of the spot welding without need for expertise . In addition, a big part of the project will be devoted to the development and the fiabilisation of a macroscopic model of dynamic behavior of the spot weldings. This model coupled with the simulation tools of the non destructive testing method will make possible the validation and the optimization of the methodology for a large range of characteristic parameters of the assemblies and spot weldings. ASAP will gather the industrial RENAULT, two SMEs EXTENDE and M2M, and two research laboratories CEA LIST and LAMIH. The expertise of these partners in complementary fields of research will make possible to lead at the end of the project to the creation of the first apparatus of the market ensuring reliable, fast and simple evaluation of the quality of the spot welding.