Construction of Interatomic Potential for B2-NiAl and Its Simple Application
|Course||Atomic and Molecular Physics|
|Keywords||NiAl alloy EAM potential bcc structure Vacancy formation energy|
Alloy material has excellent performance, widely used in many other areas of the energy, chemical, metallurgical, and NiAl alloy as a high temperature structural material has broad application prospects, especially in the aerospace industry, but its drawback is that the room temperature ductility Poor, high temperature strength is low, limiting its application to a certain extent. The microscopic mechanism of metal materials performance depends on the composition, structure and alloying elements, from the atomic level to affect the performance of the NiAl alloy by the attention. Interatomic potentials based computer simulation of the atomic and molecular level research material properties, and be able to provide help for the understanding of materials at the atomic level, which also provides a study of the material microstructure method, so you can find the precise description of the interaction of a potential function between atoms is very necessary. This article provides an overview of the main types that apply to the interaction potential between the metal atoms and development, and a brief description of the interatomic interaction potential based computer modeling methods and the development of the Embedded Atom Method (EAM) potential model constructed EAM potential between atoms of Ni, Al, and its type B2 NiAl alloys, and their lattice constants, binding energy, no relaxation vacancy formation energy, experimental data of elastic constants and the anisotropy ratio of the pure metal Ni, Al, and NiAl alloy EAM potential. Constructed in order to test the reliability of the potential binding energy curve as a reference to Rose, are compared to obtain a satisfactory result. This paper the potential function truncating truncation distance of the potential function greater impact the performance of the potential function calculated combination of Ni, Al, and NiAl alloy, Al, and NiAl alloy binding energy with the experimental values ??of well, the binding energy of Ni relative deviation with the experimental value is too large. Ni, Al and NiAl alloy structural stability calculation results show that the Ni and Al fcc (hcp) structure stable than the bcc structure, while the the NiAl alloy bcc structure is more stable than the fcc (hcp) structure, in line with the facts. Calculation of the single vacancy formation energy, Al, and NiAl alloy vacancy formation well with the experimental values ??of Ni, Al and NiAl alloy, Ni value is less than ideal, the binding energy of Ni and the vacancy formation energy with the experimental data Causes of deviation between the calculated results of some theoretical.