Issue 45

G. Giuliano et alii, Frattura ed Integrità Strutturale, 45 (2018) 164-172; DOI: 10.3221/IGF-ESIS.45.14 168 Figure 7 : Some stages of the forming test. N UMERICAL ACTIVITY he FEM modeling was performed using the MSC.Marc 2005, a commercial calculation code. Modeling required a series of steps: 1. Drawing of the sheet and the used dies; 2. Subdivision of the deformable body into finite elements; 3. Definition of constraint conditions; 4. Definition of the material properties and the formability limit curve, 5. Definition of contact and friction conditions. The previously described forming process was analyzed considering both a three-dimensional analysis (using shell elements) and a two-dimensional analysis (using axisymmetric elements). Fig. 8 shows the design of the used equipment (punch and die) as well as the discretized sheet metal in finite elements by both shell elements and axisymmetric elements. (a) (b) Figure 8 : Drawing of the used equipment (punch and die) and of the sheet discretized with finite elements of the shell type (a) and the axisymmetric type (b) . T