ATOMISTIC SIMULATIONS FOR Ni/Al INTERMETALLICS

作     者：BASKES M. I.(Sandia National Laboratories, Livermore, Califormia) 

作者机构：Sandia National Lab Livermore California United States 

出 版 物：《Acta Metallurgica Sinica(English Letters)》 (金属学报（英文版）)

年 卷 期：1995年第8卷第Z1期

页      面：287-298页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

主　　题：intermetallics atomistic calculations,hydrogen embrittlement 

摘      要：A large number of Embedded Atom Method (EAM) potentials have been developed for the Ni/Al system. These potentials are compared to a common data base. It is found that there is significant difference in quality in these potentials. One of the potentials has also been extended to represent the properties of hydrogen in Ni/Al intermetallics. This potential describes the solution and migration behavior of hydrogen in both Ni and Al.A number of calculations using the Ni/Al/H potential have been performed. It is found that hydrogen strongly prefers sites in Mi3AI that are surrounded by 6 Ni atoms. Calculations of trapping of hydrogen to a number of grain boundaries in Ni3Al have been performed as a function of hydrogen chemical potential at room temperature. The failure of these bicrystals under tensile stress has been examined and will be compared to the failure of pure Mi3AI *** order to investigate the potential embrittlement of γ/γ alloys, trapping of hydrogen to a spherical Hi3Al precipitate in Ni as a function of chemical potential at room temperature has been calculated. It appears that the boundary is not a strong trap for hydrogen, hence embrittlement in these alloys is not primarily due to interactions of hydrogen with the γ/γ interface. (Supported by the U. S. DOE through Contract DE-AC04-94AL85000.)