[P2-54] Component-wise Effect of Incompatibility Tensor on Misorientation Development in Lath Block Structure Model based on FTMP
Modeling complex microstructures, e.g., those like lath martensite structures in high Cr ferritic heat resistant steels, are one of the critical issues in multiscale modeling of materials, although neither conventional schemes exist nor effective methodologies have been developed to date. In the present study, FTMP (Field Theory of Multiscale Plasticity)-based Di-CAP (Deformation-induced Context-dependent Autonomic Pluripotency) concept is applied to computationally fabricate complex microstructured samples to be further utilized in various deformation analyses based on, e.g., FEM. Here, we focus on the process of modeling single lath-block structures, which can be obtained in preliminary bi-axial compression analyses, provided the corresponding eigenstrain distributions based on the Bain lattice correspondence is initially introduced. One of the keys for the lath-block modeling is the development of misorientation across the lath boundaries, roughly satisfying K-S variant, together with the attendant internal stress fields. FTMP-based approach exhibits spontaneous evolution of such misorientation when substantial contribution of the incompatibility tensor is introduced in the hardening law. Here we decompose the incompatibility tensor into (a)pure deformation and pure rotation, (b)edge and screw, and (c)spherical (isotropic) and deviatoric components, respectively, to examine the mechanisms for the misorientation developments. Analyses are conducted using two basic models for a single lath block structure, i.e., vertical and horizontal models, where lath sub-blocks are aligned vertically and horizontally to the [111] axis, respectively. Demonstrated for (a) is that the pure deformation part shows relatively larger contributions to the misorientation developments, while, for (b), dominant contributions of the screw component are confirmed. For (c), on the other hand, the weighted spherical part is shown to have weak but basically the same contribution.