A LOAD PERTURBATION METHOD OF EXAMINING DYNAMIC STRAIN-AGING

Load perturbation tests carried out on a 6063 Al-Mg-Si alloy under loa d rate control verify the predictions of a constitutive model proposed earlier to describe the mechanical response in the dynamic strain age ing regime. The verification is based on a comparison of the measureme nts with the analytical solution of linearlized constitutive equations for small perturbations as well as with numerical solutions for the f ull nonlinear constitutive model. The possibility of using this type o f perturbative testing for accurate determination of the onset of plas tic instability is discussed.