The U-Bending Forming of Aluminum Foam Sandwich Panels

The U-bending process of aluminum foam sandwich (AFS) is investigated, and a punch bending test is carried out in this paper. We discussed the bending deformation mode and generated the load & stroke curve of AFS panel by experiments. Macroscopic and microscopic punch forming mechanisms of AFS panels are analyzed by testing experiments and plasticity theory. We study the major deformation defects of AFS forming such as the delamination between the panel and the foam core, the excessive thinning of panels in the round corner, and shear stress cracks of the foam core. A conclusion is drawn on the panels variable blank holder force (VBHF) and the striking block control on the round corner, which would promote the forming technology of AFS.