Open-source implementations and comparison of explicit and implicit crystal-plasticity finite element methods

• Comparison of two open-source user-material implementations of rate-dependent CPFEM in Abaqus/Explicit and Abaqus/Standard. • Study of the variation of element size and strain rate on the efficiency of each implementation. • Effective implicit return mapping algorithm uses line search and power-law modification to ensure robust convergence. In this study, two state-of-the-art implementations of the rate-dependent Crystal Plasticity Finite Element Method (CPFEM) as user material subroutines in the finite element solvers Abaqus/Explicit and Abaqus/Standard (Implicit) are presented. Adaptive substepping in the explicit solver and line-search stabilized implementation in the implicit solver enable fast and stable calculations also for small strain-rate sensitivities. A comparative analysis of simulation results is made and computation times of the two implementations are compared and discussed, including the use of reduced-integration elements and mass scaling for the explicit solver. It is identified under which conditions the explicit or the implicit solver is preferred.