The effect of H impurity on the misfit dislocation in Ni-based single-crystal superalloy is investigated using the molecular dynamic simulation. It includes the site preferences of H impurity in single crystals Ni and...The effect of H impurity on the misfit dislocation in Ni-based single-crystal superalloy is investigated using the molecular dynamic simulation. It includes the site preferences of H impurity in single crystals Ni and Ni3Al, the interaction between H impurity and the misfit dislocation and the effect of H impurity on the moving misfit dislocation. The calculated energies and simulation results show that the misfit dislocation attracts H impurity which is located at the γ/γ′ interface and Ni3Al and H impurity on the glide plane can obstruct the glide of misfit dislocation, which is beneficial to improving the mechanical properties of Ni based superalloys.展开更多
Nanograins are characterized by a typical grain size from 1 to 100 nm. Molecular dynamics simulations have been carried out for the nanograin sphere with the diameters from 1.45 to 10.12 nm. We study the influence of ...Nanograins are characterized by a typical grain size from 1 to 100 nm. Molecular dynamics simulations have been carried out for the nanograin sphere with the diameters from 1.45 to 10.12 nm. We study the influence of grain size on structure and diffusion properties of the nanograins. The results reveal that as the grain size is reduced, the fraction of grain surface increases significantly, and the surface width is approximately constant; the mean atomic energy of the surface increases distinctly, but that of the grain interior varies insignificantly; the diffusion coefficient is increased sharply, and the relation of the diffusion coefficient and the grain size is close to exponential relation below 10 nm.展开更多
Using linear muffin-tin orbitals method with atomic sphere approximation,the interface electronic structure of Ge/ZnSe(111)has been studied.The density of states,local density of states as well as local partial densit...Using linear muffin-tin orbitals method with atomic sphere approximation,the interface electronic structure of Ge/ZnSe(111)has been studied.The density of states,local density of states as well as local partial density of states are presented.The interface electronic structure and the interaction characteristics between interface atoms are analyzed.The results show a significant effect of the interface atomic arrangement on the electronic structures.展开更多
基金supported by the National Basic Research Program of China (Grant No.2011CB606402)the National Natural Science Foundation of China (Grant No.51071091)
文摘The effect of H impurity on the misfit dislocation in Ni-based single-crystal superalloy is investigated using the molecular dynamic simulation. It includes the site preferences of H impurity in single crystals Ni and Ni3Al, the interaction between H impurity and the misfit dislocation and the effect of H impurity on the moving misfit dislocation. The calculated energies and simulation results show that the misfit dislocation attracts H impurity which is located at the γ/γ′ interface and Ni3Al and H impurity on the glide plane can obstruct the glide of misfit dislocation, which is beneficial to improving the mechanical properties of Ni based superalloys.
基金supported by the National Naturl Science Foundation of China(No.10172088)the Potdoctoral Saience Foundation of China
文摘Nanograins are characterized by a typical grain size from 1 to 100 nm. Molecular dynamics simulations have been carried out for the nanograin sphere with the diameters from 1.45 to 10.12 nm. We study the influence of grain size on structure and diffusion properties of the nanograins. The results reveal that as the grain size is reduced, the fraction of grain surface increases significantly, and the surface width is approximately constant; the mean atomic energy of the surface increases distinctly, but that of the grain interior varies insignificantly; the diffusion coefficient is increased sharply, and the relation of the diffusion coefficient and the grain size is close to exponential relation below 10 nm.
文摘Using linear muffin-tin orbitals method with atomic sphere approximation,the interface electronic structure of Ge/ZnSe(111)has been studied.The density of states,local density of states as well as local partial density of states are presented.The interface electronic structure and the interaction characteristics between interface atoms are analyzed.The results show a significant effect of the interface atomic arrangement on the electronic structures.
