Control arm for a torsion bar, and torsion bar

The invention relates to a control arm for a torsion bar for a vehicle, comprising a first part (1) of a first material (for example, aluminium), and a second part (21, 22) of a second material (for example, steel), the first material being more lightweight than the second material. This hybrid composition allows making the control arm lighter without relinquishing good mechanical characteristics and/or an attachment by welding to the central crosspiece (3) of a torsion bar.