The aim of this case study was to reduce the thermal and acoustic insulation parts’ cracking during forming.
Two automotive parts reproducing the most common problems in serial production were selected in this case study to understand if the crack problems were originated because of the formability of the materials and figure out which material parameters affect more to the formability process.
Under the framework of the project, fracture toughness by means of the Essential Work of Fracture methodology, was analysed in OK and NO OK aluminium material specimens that show yielding phenomenon at the crack tip during fracture.
On the other hand, the examination of the mechanical behaviour of smooth and embossed metal sheets was carried out with experimental methods including standard tensile tests, the Nakajima FLC test and ARGUS (by GOM) scanning to compare the results of numerical simulation and real part. This allowed to quantify the plastic deformation of the material during the process to minimise the impact it will have on subsequent forming operations. It also permitted to propose theoretical models to predict the deformation curves evolution under different scenarios, allowing the production process to be optimised and reducing the cost of poor quality resulting from cracks.
Finally, Estamp created an internal library database and performed simulations with the Pam-Stamp software, to correlate old simulations and old material data with the material parameters resulting from the performed tests.
