Kink Modeling and Simulations Based on Field Theory of Multiscale Plasticity (FTMP) Part II: Implicit Kink Model and Scale-Free Treatment

Abstract

We discuss not only kink formations but also the attendant primary strengthening taken place during the formation processes, by proposing anew an “Implicit” kink model based on Field Theory of Multiscale Plasticity (FTMP) only by utilizing the incompatibility tensor-incorporated Rank-1 degrees of freedom in the hardening law of the slip constitutive equation. Demonstrated is either realistically inhomogeneous kink field morphologies and successfully-raised flow stress level throughout the deformation, with the help of prescribed soft/hard structure accompanied by initial misorientations. A preliminary attempt is also made for identifying the critical roles of the empirically-found “scale-free” nature in the AE characteristics, based on the proposed model combined with the interaction field formalism in FTMP, resulting in further improved kink morphologies as well as slightly increased flow stress level.

Fig. 11 Summary of simulation results with enhanced contribution of the incompatibility DOFs, plus artificially-introduced “scale-free” nature, displaying (a) stress-strain curve, (b) energy return map (at strain of 0.015), snapshots of countors for (c) rotation angle (absolute value), (d) elastic strain energy, and (e) incompatibility (trace), respectively.