Effect of Re on lattice trapping in γ′-Ni3Al cracks by atomistic simulation

Molecular dynamics simulations of dopant effects on lattice trapping of cracks in Ni matrix*

“…Such setup showed reliable results in previous studies. [4,13,29,34] To further confirm this setup reliability, we studied three different random distributions of Re atoms at 3 at.% doping level. The deviations of the lattice and elastic constants as well as surface energy and lattice trapping limits for these distributions were negligible, which confirms the reliability of the current random doping scheme chosen in this work.…”

“…The EAM potentials typically provide reasonable results in describing the dislocations or/and crack systems of the Ni-based superalloys. [4,13,15,18,29,30,34] The 116107-2 MD simulations were performed by using the XMD program. [44] During the lattice trapping modeling, the cracks were firstly simulated under different loads, after which the atoms at the crack tips were fully relaxed by using the boundary condition described in Subsection 2.1.…”

“…However, this can be achieved by using the molecular dynamics (MD) method, a powerful and reliable approach (especially when combined with the EAM potentials) to solve the above problem and to predict the superalloy properties. [4,13,29,[34][35][36][37][38][39] Re, Ru, and Co dopants predominantly accumulated in the γ phase, while W was observed in both γ and γ phases. [40,41] Therefore, this work focused on building a model with random substitution of Ni by 1 and 3 at.% of X (X = Re, Ru, Co or W) in the γ matrix.…”

“…[18][19][20][21][22][23][24][25][26][27] Our previous work reported the lattice trapping limit increased for the Ni or Ni 3 Al cracks when Re or W was added and that W incorporation yielded much stronger effects for the Ni 3 Al cracks. [4,13,15] Other reports indicated the effect of Co on the crack propagation along the γ/γ interface was minimal. [28,29] In general, Ni matrix strengthening mechanisms involving solid solution formation (with Co, Mo, W, Re, and Ru dopants) are complex.…”

“…[9][10][11][12] Moreover, the directions of the crack front and propagation, as well as the interatomic potential and the material's structure components, also affect the lattice trapping limit and range. [13][14][15][16][17] Because of the industrial importance of the Ni-based SC superalloys, understanding their brittle fracture behavior upon cracking is essential. Thus, research on crack lattice trapping of Ni matrix is needed.…”