A numerical study into element type and mesh resolution for crystal plasticity finite element modeling of explicit grain structures

A large number of massive crystal-plasticity-finite-element (CPFE) simulations are performed and post-processed to reveal the effects of element type and mesh resolution on accuracy of predicted mechanical fields over explicit grain structures. A CPFE model coupled with Abaqus/Standard is used to simulate simple-tension and simple-shear deformations to facilitate such quantitative mesh sensitivity studies. A grid-based polycrystalline grain structure is created synthetically by a phase-field simulation and converted to interface-conformal hexahedral and tetrahedral meshes of variable resolution. Procedures for such interface-conformal mesh generation over complex shapes are developed. FE meshes consisting of either hexahedral or tetrahedral, fully integrated as linear or quadratic elements are used for the CPFE simulations. It is shown that quadratic tetrahedral and linear hexahedral elements are more accurate for CPFE modeling than linear tetrahedral and quadratic hexahedral elements. Furthermore, tetrahedral elements are more desirable due to fast mesh generation and flexibility to describe geometries of grain structures.

Automated summary

Numerous CPFE simulations were conducted to investigate the effects of element type and mesh resolution on the accuracy of predicted mechanical fields over grain structures, showing that quadratic tetrahedral and linear hexahedral elements are more accurate for CPFE modeling compared to linear tetrahedral and quadratic hexahedral elements. Tetrahedral elements are preferred due to their speed in mesh generation and flexibility in describing complex grain geometries.