A statistical analysis of grain boundary energy anisotropy in body-centered cubic metal

Abstract Grain boundary (GB) energy plays a crucial role in determining the physical and mechanical properties of polycrystalline materials, making it a key factor in the optimization of materials through GB engineering. This study computes the energies of 12,062 tilt and twist GBs in body-centered cubic (BCC) Fe using atomistic simulation. The resulting dataset facilitates a statistical analysis of GB energy anisotropy and comparison with those already revealed in face-centered cubic (FCC) Al. Results indicate that the energies of tilt and twist GBs in Fe overall increase with misorientation angle ( θ ) before plateauing. Tilt GB energies decrease as the misorientation axis ( O ) shifts from the center to edges and then to corners of the stereographic triangle, while twist GB energies vary smoothly, with a notable energy valley near 〈110〉 axis. The GB-plane orientation ( n ) dependency of boundary energy should be interpreted from the view of the surface energy corresponding to GB-plane. The relative significance of crystallographic parameters to GB energy is ranked as θ > n >> O , with the coincidence index primarily identifying local energy cusps on the energy versus angle curve. Trends in GB energy relative to crystallography in BCC structures highly resemble those in FCC structures. However, it seems impossible to determine a specific scaling factor between GB energies in two structures or correlate this factor with any material properties. This study can provide crucial data for GB energy fitting and simulations of thermodynamic behaviors related to GBs.