First-principles study on the mechanical properties of interstitial solid solution Aluminum–Boron alloy

Abstract

The sputtering Al-B alloy film exhibits a unique growth structure and a high strengthening efficiency. In this study, the first-principles method was used to investigate the effect of addition B element on the mechanical properties of Al-B alloys, including the elastic properties, anisotropy, ideal shear strength, generalized stacking fault energy (GSFE), and dislocation core. Results indicate that the solid solution of B slightly decreases the elastic modulus of the alloy and decreases the ideal shear strength. Thus, the anisotropic tendency weakens, GSFE substantially increases, and the Peierls stress and Peierls barrier energy substantially increase. Therefore, the introduce of B has little effect on the intrinsic properties of the alloy, but the interstitial solid solution of B greatly increases the dislocation initiation energy, which limits the initiation and movement of dislocation, and has an important contribution to the strengthening effect.