One of the main applications for extrusions in the automotive sector is crash structures including crash rails, crash cans, bumpers, and structural body components. The objective is usually to optimize the energy absorption capability for a given structure weight. The ability to extrude thin wall multi-void extrusions contributes to this goal. However, the alloy used also plays a significant role in terms of the ability to produce the required geometry, strength which to a large extent controls the energy absorption capability, and the “ductility” or fracture behavior which controls the strain that can be applied locally during crush deformation before cracking. This paper describes results of a test program to examine the crush behavior of a range of alloys supplied by Rio Tinto Aluminium for automotive applications, as a function of processing parameters including artificial aging and quench rate.