Development of aluminum alloy 6063 T6 and T7 material models and their effects on energy-absorbing characteristics of cross-axial members

Abstract

This article presents a new and detailed study on the characterization of material properties of AA 6063 T6 and T7 tempers and their effects on crushing response and energy absorption in a novel tubular structural member for design for crashworthiness purposes. These properties were characterized into three regions: the elastic, the uniform plastic, and the ductile damage regions. Standard tensile tests were used to ascertain the elastic and plastic properties up until uniaxial instability. To characterize the ductile damage, a phenomenological model was employed using a decaying exponential fit of triaxial stresses versus equivalent plastic strain data obtained from finite element and experimental models of flat notched specimens. A new theoretical model for predicting the crushing behavior of the novel cross tube was developed. A numerical, experimental, and theoretical comparison of the mean crushing force for novel extruded crossshaped specimens of both tempers was also presented. The results of this study provide valuable insights into the applications of T6 and T7 tempers of aluminum as energy-absorbing materials for novel cross-shaped structural members for improved crashworthiness.