Ab-initio study of atomic structure and mechanical behaviour of $\mathit{Al}/\mathit{Fe}$ intermetallic interfaces

Abstract

First-principles virtual tensile and shear test calculations have been performed to Al(0 0 $\overline{3}$)//$\alpha$-AlFeSi(0 0 1) and Al(0 $\overline{1}$ 4)//Fe₄Al₁₃(1 0 $\overline{1}$) interfaces by the ab initio pseudo potential density functional theory method. Work of separation, ultimate tensile strength and shear strength of bulk and interface structures were calculated. The Al(0 0 $\overline{3}$)/$\alpha$-AlFeSi(0 0 1) interface showed higher tensile strength than the Al(0 $\overline{1}$ 4)//Fe₄Al₁₃(1 0 $\overline{1}$) interface structure. Moreover, interface calculations revealed a charge depletion region in the second layer of the Fe₄Al₁₃ structure, which caused lower work of separation. Furthermore, shear calculations showed stronger shear strength for the Al(0 $\overline{1}$ 4)//Fe₄Al₁₃(1 0 $\overline{1}$) interface than for the Al(0 0 1)//$\alpha$-AlFeSi(0 0 1) interface structure.