Influence of orientation on crack propagation of aluminum by molecular dynamics

The crack growth behavior of single crystal aluminum is investigated under tensile test at room temperature by molecular dynamics simulations. Three crack models are selected, which are [001](010) crack, ( $$\overline{1}$$ 1 ¯ 10)[110] crack and [11 $$\overline{2}$$ 2 ¯ ](111) crack. The results present that the mechanical properties and deformation mechanisms are significantly influenced by the orientation of initial crack. The [ $$\overline{1}$$ 1 ¯ 10] (110) crack has the maximum yield strength, the [11 $$\overline{2}$$ 2 ¯ ] (111) crack has the maximum elastic modulus. The [001](010) crack propagates in the form of micro-cracks and shows ductility fracture, and the main deformation mechanisms are blunting and slip bands at crack tip. The ( $$\overline{1}$$ 1 ¯ 10)[110] crack evolves into a void with the loading increasing, presents ductile extension, and the slip bands divide the crystal structure into mesh region. For (111) [11 $$\overline{2}$$ 2 ¯ ] crack, it has very good toughness and ductility and can effectively reduce structural damage caused by crack propagation. Graphical abstract The initial models of crack. (a) [001](010) crack, (b) [110] (110) crack (c) [11 2] (111) crack