Point-defect and threshold displacement energies in Ni3Al I. Point-defect properties

Abstract The energy and volume change associated with the creation of point defects in Ni3Al have been calculated by computer simulation using a modified version of the many-body potentials of Vitek, Ackland and Cserti. The potentials have been adjusted to provide a better description of the interaction between atoms at separations inside the normal nearest-neighbour spacing. This region is important for interstitial properties and the interaction of atoms in displacement events associated with radiation damage. The properties of point defects in the pure metals Al and Ni are in good agreement with known values. For Ni3Al, the properties of the Ni defects are very close to those found by Caro, Victoria and Averback with the embedded-atom potentials for Ni3Al of Foiles and Daw, and the most stable interstitial, in particular, is the Ni-Ni⟨100⟩ dumbbell centred on a Ni site in the {100} planes which contain only Ni atoms. For the Al and antisite defects, however, the model used here gives different results....

[1]  R. A. Johnson,et al.  Simple embedded atom method model for fcc and hcp metals , 1988 .

[2]  P. Ehrhart.  The configuration of atomic defects as determined from scattering studies , 1978 .

[3]  A. J. Cable,et al.  High-velocity impact phenomena , 1970 .

[4]  M. Gillan.  Calculation of the vacancy formation energy in aluminium , 1989 .

[5]  M. Baskes,et al.  Embedded-atom method: Derivation and application to impurities, surfaces, and other defects in metals , 1984 .

[6]  Defect Clusters in B.C.C. Metals,et al.  Point defects and defect interactions in metals , 1982 .

[7]  James F. Ziegler,et al.  Refined universal potentials in atomic collisions , 1982 .

[8]  Foulkes,et al.  Tight-binding models and density-functional theory. , 1989, Physical review. B, Condensed matter.

[9]  M. Finnis,et al.  A simple empirical N-body potential for transition metals , 1984 .

[10]  Joshua R. Smith,et al.  Universal features of the equation of state of metals , 1984 .

[11]  G. Ackland,et al.  Validity of the second moment tight-binding model , 1988 .

[12]  J. Soler,et al.  Defect energetics in aluminium , 1991 .

[13]  M J Fluss,et al.  Measurements of the vacancy formation enthalpy in aluminum using positron annihilation spectroscopy , 1978 .

[14]  G. Ackland,et al.  Simple N-body potentials for the noble metals and nickel , 1987 .

[15]  F. Young.  Interstitial mobility and interactions , 1978 .

[16]  M. Daw,et al.  Application of the embedded atom method to Ni_3Al , 1987 .

[17]  J. Cserti,et al.  Atomistic Modeling of Extended Defects in Metalic Alloys: Dislocations and Grain Boundaries in Ll2 Compounds , 1990 .

[18]  M. Doyama,et al.  Study of vacancies in the intermetallic compound Ni3Al by positron annihilation , 1984 .

[19]  Vítek,et al.  Many-body potentials and atomic-scale relaxations in noble-metal alloys. , 1990, Physical review. B, Condensed matter.

[20]  J. Campbell,et al.  Temperature dependence of positron trapping in silver and nickel , 1977 .

[21]  A. Caro,et al.  The effect of electronic energy loss on the dynamics of thermal spikes in Cu , 1991 .

[22]  D. Bacon,et al.  Point-defect and threshold displacement energies in Ni3Al II. Events at the displacement threshold , 1993 .