Inventors:
- Detroit MI, US
Benjamin P. Hunault - Grand Blanc MI, US
John G. Peck - Waterford MI, US
Assignee:
GM GLOBAL TECHNOLOGY OPERATIONS LLC - Detroit MI
International Classification:
B21D 47/00
Abstract:
A method of forming a surface in a panel includes positioning a panel blank between a stationary die and a moveable die of a die set, and moving the moveable die toward the stationary die to deform the panel blank therebetween. Positive stresses in the panel blank are maintained in the region of the panel blank that will form the surface by forming a bead along a length of the surface to be formed in the panel blank, as the moveable die moves toward the stationary die. The moveable die continues to move toward the stationary die, while maintaining positive stresses in the panel blank in the region of the panel blank that will form the surface, to further deform the panel blank into a formed shape that includes the surface.