Microscopic phase field simulation for the influence of Ni-Al ordering energy on ordering behavior of Ni₇₅Al₁₃Cr₁₂ alloy atoms

The influence of Ni-Al ordering energy from the first to the fourth layer on the atom long range order progress in Ni₇₅Al₁₃Cr₁₂ alloy was investigated by microscopic phase field model. Results show that as the first Ni-Al ordering energy increased the ordering and the clustering degree of Al atoms increased, while that of Cr atoms alternated with time steps. As the second Ni-Al ordering energy increased, the ordering and the clustering degree of Al atoms decreased, while that of Cr atoms alternated, too, which was opposite to the change of the first layer. As the third Ni-Al ordering energy increased, the degree and speed of the ordering and the clustering of Al and Cr atoms were all increased. And the influence of the fourth Ni-Al ordering energy was contrary with the third one. Under the same change of ±10 meV, the influence of Ni-Al ordering energy on the ordering and the clustering of Al atoms became more obvious as increasing of the number of the layer; the influence of the third Ni-Al ordering energy on the ordering and the clustering of Cr atoms was maximum; while the influence of the second Ni-Al ordering energy on the Cr ordering was minimum, and the influence of the fourth ordering energy on the clustering of Cr atoms was minimum.