Roll Forming Characteristics and Press Formability of Hexagonal Dimple Pattern Sheet

Abstract

The proposed hexagonal dimple pattern sheet (HDP sheet) is an effective lightweight material for the body and other parts of automobiles, because of its increased bending strength and rigidity compared with flat sheets. In this study, the deformation state of HDP sheets formed by roll forming using aluminum alloy sheets has been experimentally examined, and their press formability has been evaluated. The roll-formed HDP sheets were shortened in the rolling direction but remained unchanged in the transverse direction. The deep drawability and shape fixability of the HDP sheets improved, but the stretchability and stretch-flanging formability deteriorated compared with those of the flat sheets. Nevertheless, as the HDP sheets became thicker, their rates of deterioration decreased.