Recently,metal-graphene nanocomposite system has aroused much interest due to its radiation tolerance behavior.However,the related atomic mechanism for the metal-graphene interface is still unknown.Further,stainless s...Recently,metal-graphene nanocomposite system has aroused much interest due to its radiation tolerance behavior.However,the related atomic mechanism for the metal-graphene interface is still unknown.Further,stainless steels with Fe as main matrix are widely used in nuclear systems.Therefore,in this study,the atomic behaviors of point defects and helium(He) atoms at the Fe(110)-graphene interface are investigated systematically by first principles calculations.The results indicate that graphene interacts strongly with the Fe(110) substrate.In comparison with those of the original graphene and bulk Fe,the formation energy values of C vacancies and Fe point defects decrease significantly for Fe(110)-graphene.However,as He atoms have a high migration barrier and large binding energy at the interface,they are trapped at the interface once they enter into it.These theoretical results suggest that the Fe(110)-graphene interface acts as a strong sink that traps defects,suggesting the potential usage of steel-graphene with multiply interface structures for tolerating the radiation damage.展开更多
The interface structure and electronic properties of Fe(110)/Al(110) are investigated by the first-principles plane-wave pseudopotential method. The interface segregation position of Si and Mg is determined, and the e...The interface structure and electronic properties of Fe(110)/Al(110) are investigated by the first-principles plane-wave pseudopotential method. The interface segregation position of Si and Mg is determined, and the effect of Mg and Si on the interface binding of Fe(110)/Al(110) is analyzed by combining the work of separation and charge density. The results show that the Fe(110)/Al(110) interface energy of FeHollow coordination is smaller and the interface structure is more stable. The Fe(110)/Al(110) interface separation surface in the form of Fe-Hollow coordination appears at the sub interface layer on the side of Al(110)near the interface. The interface structure of Mg and Si segregation is similar to that of undoped alloy elements.The calculations also suggest that Mg and Si segregate on the Al(110) side of the interface and occupy the Al lattice on the Al(110) side. The segregation of Mg and Si elements will reduce the interface binding, primarily because the Fe-Si bond and Fe-Mg bond are weaker than Fe-Al bond.展开更多
Preparing method and processing of Tb-Dy-Fe alloy samples with [110] axial orientation as well as their magnetostrictive properties have been studied. It has been found that the magnetostrictive strains of polycrystal...Preparing method and processing of Tb-Dy-Fe alloy samples with [110] axial orientation as well as their magnetostrictive properties have been studied. It has been found that the magnetostrictive strains of polycrystal samples with [110] axial orientation can reach (1550-1900) ×10~-6 in a low magnetic field less than 80 kA/m, which are equal to or somewhat better than that of the polycrystal samples with [112] axial orientation.展开更多
The density functional theory（DFT） and self-consistent periodic calculation were used to investigate the C2Hx（x = 4～6） species adsorption on the Fe（110） surface. The adsorption energy and equilibrium geometry o...The density functional theory（DFT） and self-consistent periodic calculation were used to investigate the C2Hx（x = 4～6） species adsorption on the Fe（110） surface. The adsorption energy and equilibrium geometry of the species C2Hx（x = 4～6） on four possible sites（top,hcp,SB and LB） on the Fe（110） surface were predicted and compared. Mulliken charges and density of states analysis of the most stable site have been discussed. It is found that the species of C2H6 and C2H5 are adsorbed strongly on the Fe（110） surface with calculated adsorption energy of -80.24 and -178.89 kJ·mol^-1 at the Fe-LB（long-bridge） ,respectively. However,the C2H4 is adsorbed strongly on the Fe（110） surface with calculated adsorption energies of -114.96 kJ·mol^-1 at the top. The results indicate that the charge transferring process can be completed by chemisorption between Fe（110） surface and the species. Moreover,the chemical bands can be formed by chemisorptions between the Fe（110） surface and the species,too.展开更多
基金Project supported by the Nuclear Power Technology Innovation Center ProgramNational Defense Science&Technology Industry,China(Grant No.HDLCXZX-2019-ZH-028)。
文摘Recently,metal-graphene nanocomposite system has aroused much interest due to its radiation tolerance behavior.However,the related atomic mechanism for the metal-graphene interface is still unknown.Further,stainless steels with Fe as main matrix are widely used in nuclear systems.Therefore,in this study,the atomic behaviors of point defects and helium(He) atoms at the Fe(110)-graphene interface are investigated systematically by first principles calculations.The results indicate that graphene interacts strongly with the Fe(110) substrate.In comparison with those of the original graphene and bulk Fe,the formation energy values of C vacancies and Fe point defects decrease significantly for Fe(110)-graphene.However,as He atoms have a high migration barrier and large binding energy at the interface,they are trapped at the interface once they enter into it.These theoretical results suggest that the Fe(110)-graphene interface acts as a strong sink that traps defects,suggesting the potential usage of steel-graphene with multiply interface structures for tolerating the radiation damage.
基金the National Natural Science Foundation of China(No.51871030)the Higher Education Science Foundation of Jiangsu Province of China (No.17KJA430006)。
文摘The interface structure and electronic properties of Fe(110)/Al(110) are investigated by the first-principles plane-wave pseudopotential method. The interface segregation position of Si and Mg is determined, and the effect of Mg and Si on the interface binding of Fe(110)/Al(110) is analyzed by combining the work of separation and charge density. The results show that the Fe(110)/Al(110) interface energy of FeHollow coordination is smaller and the interface structure is more stable. The Fe(110)/Al(110) interface separation surface in the form of Fe-Hollow coordination appears at the sub interface layer on the side of Al(110)near the interface. The interface structure of Mg and Si segregation is similar to that of undoped alloy elements.The calculations also suggest that Mg and Si segregate on the Al(110) side of the interface and occupy the Al lattice on the Al(110) side. The segregation of Mg and Si elements will reduce the interface binding, primarily because the Fe-Si bond and Fe-Mg bond are weaker than Fe-Al bond.
文摘Preparing method and processing of Tb-Dy-Fe alloy samples with [110] axial orientation as well as their magnetostrictive properties have been studied. It has been found that the magnetostrictive strains of polycrystal samples with [110] axial orientation can reach (1550-1900) ×10~-6 in a low magnetic field less than 80 kA/m, which are equal to or somewhat better than that of the polycrystal samples with [112] axial orientation.
基金Project supported by the Natural Science Foundation of Education Committee of Chongqing (No. KJ091311)
文摘The density functional theory（DFT） and self-consistent periodic calculation were used to investigate the C2Hx（x = 4～6） species adsorption on the Fe（110） surface. The adsorption energy and equilibrium geometry of the species C2Hx（x = 4～6） on four possible sites（top,hcp,SB and LB） on the Fe（110） surface were predicted and compared. Mulliken charges and density of states analysis of the most stable site have been discussed. It is found that the species of C2H6 and C2H5 are adsorbed strongly on the Fe（110） surface with calculated adsorption energy of -80.24 and -178.89 kJ·mol^-1 at the Fe-LB（long-bridge） ,respectively. However,the C2H4 is adsorbed strongly on the Fe（110） surface with calculated adsorption energies of -114.96 kJ·mol^-1 at the top. The results indicate that the charge transferring process can be completed by chemisorption between Fe（110） surface and the species. Moreover,the chemical bands can be formed by chemisorptions between the Fe（110） surface and the species,too.
