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Semi-Empirical Force-Field Model for the Ti_1-xAl_xN (0 ? x ? 1) System.

ABSTRACT: We present a modified embedded atom method (MEAM) semi-empirical force-field model for the Ti_1-xAl_xN (0 ? x ? 1) alloy system. The MEAM parameters, determined via an adaptive simulated-annealing (ASA) minimization scheme, optimize the model's predictions with respect to 0 K equilibrium volumes, elastic constants, cohesive energies, enthalpies of mixing, and point-defect formation energies, for a set of ?40 elemental, binary, and ternary Ti-Al-N structures and configurations. Subsequently, the reliability of the model is thoroughly verified against known finite-temperature thermodynamic and kinetic properties of key binary Ti-N and Al-N phases, as well as properties of Ti_1-xAl_xN (0 < x < 1) alloys. The successful outcome of the validation underscores the transferability of our model, opening the way for large-scale molecular dynamics simulations of, e.g., phase evolution, interfacial processes, and mechanical response in Ti-Al-N-based alloys, superlattices, and nanostructures.

SUBMITTER: Almyras GA

PROVIDER: S-EPMC6356630 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Semi-Empirical Force-Field Model for the Ti1-xAlxN (0 ≤ x ≤ 1) System.

Almyras G A GA Sangiovanni D G DG Sarakinos K K

Materials (Basel, Switzerland) 20190110 2

We present a modified embedded atom method (MEAM) semi-empirical force-field model for the Ti1-xAlxN (0 ≤ x ≤ 1) alloy system. The MEAM parameters, determined via an adaptive simulated-annealing (ASA) minimization scheme, optimize the model's predictions with respect to 0 K equilibrium volumes, elastic constants, cohesive energies, enthalpies of mixing, and point-defect formation energies, for a set of ≈40 elemental, binary, and ternary Ti-Al-N structures and configurations ...[more]

PMID: 30634593

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Semi-Empirical Force-Field Model for the Ti_1-xAl_xN (0 ? x ? 1) System.

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Semi-Empirical Force-Field Model for the Ti<sub>1-x</sub>Al<sub>x</sub>N (0 ≤ x ≤ 1) System.

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Semi-Empirical Force-Field Model for the Ti1-xAlxN (0 ? x ? 1) System.

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Semi-Empirical Force-Field Model for the Ti<sub>1-x</sub>Al<sub>x</sub>N (0 ≤ x ≤ 1) System.

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OmicsDI is part of the ELIXIR infrastructure

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Semi-Empirical Force-Field Model for the Ti_1-xAl_xN (0 ? x ? 1) System.