Abstract: A cross-member for a motor-vehicle twist-beam axle suspension includes a single piece of steel that defines a closed cross-section and integrally forms a middle section, a pair of end sections, and a pair of joining sections. The middle section has a center axis extending along a curvilinear path lying in a first plane and a squashed portion extending in a second plane inclined to the first plane. The end sections are adapted to be securely connected to respective trailing arms of the twist-beam axle suspension. Each of the joining sections is interposed between the middle section and the respective end section and defines an opposite concavity with respect to the middle section. A twist-beam axle suspension for a motor vehicle includes the cross-member and a pair of trailing arms. A method produces the cross-member for a motor-vehicle twist-beam axle suspension.

Abstract: The twist-beam axle (10) comprises a central cross-member (11) compliant to torsion and a pair of trailing arms (12) fixed to side end portions (11a) of the cross-member (11) for articulated connection of the axle to the vehicle body and for support of the rear wheels. Each trailing arm (12) is formed by a pair of first, transversely inner half-shells (18, 19), that is, a front half-shell and a rear half-shell, respectively, securely connected to each other and to the respective end (11a) of the cross-member (11), and by a second transversely outer half-shell (20), securely connected to the pair of first half-shells (18, 19) so as to form therewith a structure having a closed cross-section.

Abstract: The member (2), particularly adapted for an arm (1) of which a motor vehicle suspension, has a box-like structure which comprises a pair of shaped portions (3, 4) disposed facing each other. Said portions are obtained from a pair of integral plate portions (3′, 4′) of a semi-finished product (2′) in the form of a shaped, essentially flat element, produced starting from a plastically deformable material in sheet form, by folding over the shaped element (2′) along at least one predetermined line (16, 17), so as to dispose the plate portions (3′, 4′) facing each other.