Predictions of the complex cyclic behavior of polycrystals using a self-consistent modeling

Motivated by a simplified self-consistent model proposed recently (Abdul-Latif, A., Dingli, J. Ph., Saanouni, K., 1999b. Elastic–inelastic self-consistent model of polycrystals. submitted), qualitative and quantitative studies are performed. The rate-dependent inelastic strain is defined at the crystallographic slip system level describing a constitutive model for fcc metallic polycrystals, while the elastic part is defined at the granular level. The elastic behavior of each grain is assumed to be compressible and isotropic. Non-linear stress–strain behavior of polycrystals under complex cyclic loading is studied using the model. Since the overall hardening behavior is well described by the model, a host of inelastic behaviors of polycrystalline metals under uniaxial and multiaxial cyclic loading paths is appropriately predicted, such as Bauschinger, ratcheting and strain memory effects as well as additional hardening due to non-proportional loading. After determining the model parameters by using two experimental data-bases, the self-consistent model is shown to successfully describe the elastic–inelastic cyclic behavior of the nickel base alloy Waspaloy and the austenitic stainless steel 316L, both at room temperature under simple and complex loading conditions.