Effect of the 3rd Dimension within the Representative Volume Element (RVE) on Damage Initiation and Propagation during Full-Phase Numerical Simulations of Single and Multi-Phase Steels.

Faisal Qayyum,Ulrich Prahl,Matthias Schmidtchen,Muhammad Umar,Rudolf Kawalla,Sergey Guk

doi:10.3390/ma14010042

Abstract

In this research, the effect of 2D and 3D Representative Volume Element (RVE) on the ductile damage behavior in single-phase (only ferrite) and dual-phase (ferrite and martensite) steels is analyzed. Physical and fitting parameters of the constitutive model for bcc-ferrite and bcc-martensite phases are adapted from the already published work. Crystal plasticity (CP) based numerical simulations without damage consideration are run and, later, ductile damage criteria for the ferrite phase is defined for all cases. The results of the non-damage (-nD-) and damage (-D-) simulations are compared to analyze the global and local differences of evolving stresses and strains. It is observed that for the same model parameters defined in all cases, damage initiation occurs at the overall higher global strain in the case of 3D compared to 2D. Based on statistical data analysis, a systematic comparison of local results is carried out to conclude that the 3D RVEs provide better quantitative and qualitative results and should be considered for such full phase simulations. Whereas 2D RVEs are simple to analyze and provide appropriate qualitative information about the damage initiation sites.

Highlights

Steel is extensively used as a structural material due to wide availability, low cost, and high strength [1]
Simulations on single-phase steel and multi-phase DP-steel were run for the case of 2D and 3D Representative Volume Element (RVE) with and without damage criteria incorporation
3D RVE considerations—in the case of single-phase steel—affect the damage evolution, and, for the case of DP-steel, 2D, and 3D RVEs with damage and non-damage criteria are simulated to observe the difference in damage initiation and propagation for the case of multi-phase materials

Summary

Introduction

Steel is extensively used as a structural material due to wide availability, low cost, and high strength [1]. The varying microstructure of steel results in varying mechanical properties [2,3]. Such varying microstructure yields different damage mechanisms, crucial for many components operating at critical loading conditions, especially in the forming industry [4,5]. The development of application-focused advanced steels requires an accurate understanding of the microstructure-property relationship and resulting damage behavior in emerging modern steels. Plastic deformation in such materials occurs due to dislocation motion or twin formation [6]. The damage evolution occurs due to the void coalescence in close proximity, forming micro-cracks

Results

Discussion

Conclusion