Modified embedded-atom method interatomic potentials for Ti and Zr

Semiempirical interatomic potentials for hcp elements, Ti and Zr, have been developed based on the MEAM (modified embedded-atom method) formalism. The new potentials do not cause the stability problem previously reported in MEAM for hcp elements, and describe wide range of physical properties (bulk properties, point defect properties, planar defect properties, and thermal properties) of pure Ti and Zr, in good agreement with experimental information. The applicability of the potentials to atomistic approaches for investigation of various materials behavior (slip, irradiation, amorphous behavior, etc.) in Ti or Zr-based alloys is demonstrated by showing that the related material properties are correctly reproduced using the present potentials and that the potentials can be easily extended to multicomponent systems.

Figure 1

Seven interstitial sites in the hexagonal closed-packed lattice.

Figure 2

Thermal linear expansion of hcp Ti in the $a$ and $c$ directions. Symbols are the present calculation and lines are experimental data (Refs. 47, 48).

Figure 3

Thermal linear expansion of hcp Zr in the $a$ and $c$ directions. Symbols are the present calculation and lines are experimental data (Ref. 49).