7. Conclusion

The experimental and numerical investigations carried out as part of this study focused on modeling the problems of hydroforming thin structures. Analyses and observations of hydroformed tubes or plates have enabled us to identify the main causes of fracture and failure during the forming process. These failures are largely the result of plastic instabilities associated with the presence of local micro-defects and non-reversible deformations, leading to the incubation or nucleation, coalescence and growth of damage.

A contribution to the modeling of elastoplastic behavior is proposed for the localization of instability zones and the assessment of damage extent. Numerical simulation has contributed to the understanding of hydroforming processes for thin structures, using the work-hardening model coupled to ductile damage. Analysis of the feasibility of complex geometries...