Relationship Between Structure and Energy of Symmetric Tilt Grain Boundaries in Ag and Ni

A. Ayadi, H. Laib, O. Khalfallah Laboratory of Microstructure and Defects in Materials (LMDM), Department of Physics, University Constantine 1, Algeria

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The objective of this study is to obtain the correlation between energy and structure of symmetric tilt grain boundaries (STGB) around a [100] axis in Ag and Ni. The atomic simulations use LAMMPS, a parallel molecular dynamics code, with the embedded atom model potential (EAM) to calculate the energies of 200 grain boundaries in FCC bicrystals of Ag and Ni. The results show a similar variation in energy as a function of misorientation for the two metals. This variation has energy minima for Σ5 and Σ13 boundaries. The grain boundaries structures, described by the structural units model, are of two types. Simple types for the STGB Σ5 and Σ13 are generally associated with low energies and a complex type for the STGB Σ65 is associated with high energies. A pairwise comparison of grain boundary energy (Ag vs. Ni) shows a correlation between the grain boundary energy and shear modulus which is consistent with the Read and Shockley model

DOI:10.12693/APhysPolA.138.528 topics: symmetric tilt grain boundaries, energy, structure, molecular dynamics (MD)