Atomistic simulations of the phase stability and elastic properties of nickel–zirconium alloys F.J. Cherne * , M.I. Baskes, R.B. Schwarz Los Alamos National Laboratory, MST-8 Structure and Property Relations, P.O. Box 1663, MS G755, Los Alamos, NM 87545, USA Abstract We study the phase stability and the elastic properties of amorphous and crystalline nickel–zirconium alloys using the modified embedded-atom method (MEAM). This binary system was chosen because it has been extensively characterizedbothinthecrystallineandamorphousphases.TheMEAMpotentialsdevelopedherepredictthemelting temperatures of pure Ni and Zr, and those of the known NiZr intermetallic compounds to better than 13%. For all known intermetallic crystalline structures, the enthalpies of formation predicted by the MEAM model compare fa- vorably to experimental data. The calculated atomic volumes show a slight negative deviation from VegardÕs law. Calculated values of the shear modulus of the amorphous phase also show good agreement with experiment. Ó 2003 Elsevier Science B.V. All rights reserved. PACS: 61.43.D; 61.20.J; 61.43.B; 62.20.D 1. Introduction The recent advent of bulk metallic glasses has stressedtheimportanceofunderstandingchemical and topological short-range order (SRO) in these materials. Because analytical techniques such as high-resolution electron microscopy provide no help in visualizing SRO in metallic glasses, this information must be derived by indirect methods, including atomistic simulations. However, for the simulations to provide a reliable visualization of SRO, one can no longer rely on atomic pair po- tentials used in past simulations. The interatomic forces must include an angular dependence and a description of local electronic transferprocesses.Asatestofthereliabilityofthe interatomic potentials, the simulations must be able to predict correctly the phase stability of all the crystalline compounds the system forms in thermodynamic equilibrium. This paper describes our efforts at obtaining reliable potentials for simulating Ni–Zr glasses. This binary system was chosen because the Ni–Zr system has been extensively characterized both in the crystalline and amorphous phases. Measure- ments of the shear modulus of amorphous Ni ð1xÞ Zr x (0:1 < x < 0:9) films using Rayleigh waves [1] have shown that the shear modulus has severalsharpmaxima.Someofthesemaximaoccur at the compositions where Ni and Zr form crys- talline intermetallic compounds. These maxima * Corresponding author. Tel.: +1-505 665 5636; fax: +1-505 667 8021. E-mail address: cherne@lanl.gov (F.J. Cherne). 0022-3093/03/$ - see front matter Ó 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S0022-3093(02)01982-8 Journal of Non-Crystalline Solids 317 (2003) 45–51 www.elsevier.com/locate/jnoncrysol