The investigation of time-dependent springback for AC170PX aluminum alloy at room temperature

Highlights: • We examine changes of the anelastic strain by different loading conditions. • We model the anelastic curves by the simplified equation based on viscoelasticity. • Anelastic strain fluctuates as the loading strain rate increases. • The anelastic strain of crystal plane is related to the crystal index. • An anisotropy in recovery behavior concerning lattice plane is discovered. The time-dependent springback and anelastic behavior of AC170PX aluminum alloy were investigated as a function of time, prescribed strains and loading strain rates by uniaxial tensile tests. In order to quantify the effect and infer its basis, the X-ray diffraction tests for the lattice-strain recovery were conducted. The measured anelastic strain accumulated in 10 h increased, as the prescribed strain went up. A non-monotonic behavior, showing a maximum anelastic recoverable strain at an intermediate strain rate followed by onset of a decreasing trend, is observed. The XRD results show the changes of different interplanar spacings in the time-dependent response do not follow the elastic law. There exists an anisotropy in recovery behavior with respect to lattice plane.