Spatial coupling in jerky flow using polycrystal plasticity

摘要: A multiscale approach including a finite element framework for polycrystal plasticity is used to model jerky flow, also known as the Portevin-Le Chatelier effect. The local constitutive behavior comprises standard description of negative strain rate sensitivity flow stress in domain instability. Due gradients inherent formulation, spatial coupling involved spatio-temporal dynamics naturally accounted model, without using any ad hoc gradient formulation. For first time, static, hopping and propagating band types are recovered constant strain-rate tests, well temporal properties serrations. associated dynamic regimes characterized found consistent with recent experimental evidence both chaos self-organized criticality Al-Mg polycrystals.