Static and dynamic crushing of aluminium profiles

Abstract

In this thesis the static and dynamic axial crushing response of an extruded two-chamber aluminium profile geometry have been studied. The materials tested were two aluminium alloys of the 6000-series, AA6063 and AA6082, both stretched to two different extents of plastic strain before heat treatment to temper T6. Material data were obtained from quasi-static tensile tests and from NaMo. Axial crushing tests were performed at quasi-static and dynamic loading conditions and were simulated with shell elements in Abaqus/Explicit. One quasi-static and one dynamic solid analysis were also run for comparison with the shell analyses. It was found that AA6082 absorbs more energy, but is less ductile than AA6063 and that 0.5% cold deformation yields higher energy absorption, but less ductility than 4% cold deformation. The dynamic tests showed a 11-15% higher mean force than the quasi-static tests, but the peak force was identical. Variations of the impact velocity of the dynamic tests did not affect the numeric results but it clearly affected the deformation of the profiles. In the numerical work, the only successful shell element analyses were the quasi-static analyses of AA6063, due to little fracture of those profiles. It was seen that the dynamic analyses should be run with solid elements.