| 摘要 |
A structural beam, particularly for use as a door pillar or a bumper of a motor vehicle, includes a one-piece elongated extruded member formed of a light metal. The member has therethrough an elongated, laterally enclosed cavity defined by elongated side walls including at least two generally parallel side walls. A deformation pressure is applied to walls extending generally transverse to the two side walls, with the result that there occurs controlled folding of the two side walls with the formation therein of folds that extend parallel to the direction of elongation of the member. Thus, the cross-sectional area of the cavity through the member is reduced. |
