The effect of precipitate-induced backstresses on plastic anisotropy: Demonstrated by modeling the behavior of aluminum alloy, 7085

The constitutive response of commercial aluminum alloy 7085, is characterized under quasistatic (0.001 s(-1)) and high strain rate (1250 s(-1)) uniaxial compression loading along the rolling, transverse, and normal directions (RD, TD and ND, respectively) and at 45 degrees to RD within the plane of the plate (henceforth denoted as 45) at different aging conditions, in order to see the effect of aging on the flow stress and plastic strain anisotropy. It is shown that with aging, the material tends towards isotropy, i.e., the in-plane plastic anisotropy is reduced. These results verify the previously hypothesized connection between precipitate induced-backstress and anisotropy. A model taking into account the kinematic hardening effect of an elastic inclusion within an elastoplastic single crystal has been incorporated into the elastoplastic self-consistent (EPSC) polycrystal modeling framework to quantitatively describe this effect of precipitates on plastic anisotropy. Finally, the plastic anisotropy, during compressive straining parallel to the normal direction, is shown to be remarkably sensitive to the initial texture.