Stability and elasticity of metastable solid solutions and superlattices in the MoN-TaN system: First-principles calculations

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F18%3A00493529" target="_blank" >RIV/68081723:_____/18:00493529 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216224:14310/18:00106542

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.matdes.2018.02.033" target="_blank" >http://dx.doi.org/10.1016/j.matdes.2018.02.033</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.matdes.2018.02.033" target="_blank" >10.1016/j.matdes.2018.02.033</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Stability and elasticity of metastable solid solutions and superlattices in the MoN-TaN system: First-principles calculations

Popis výsledku v původním jazyce

In order to develop design rules for novel nitride-based coatings, we investigate trends in thermodynamic, structural, elastic, and electronic properties ofMo1-xTaxNsingle-phase alloys together with (MoN)(1-x)/(TaN)(x) superlattices. Our calculations predict that hexagonal Mo1-xTaxN are the overall most stable ones, followed by the disordered cubic solid solutions and superlattices. The disordered cubic systems are energetically clearly favoured over their ordered counterparts. To explain this unexpected phenomenon, we perform an in-depth structural analysis of bond-lengths and angles, revealing that the disordered phase is structurally between the NaCl-type and the hexagonal NiAs-type modifications. Similarly, the bi-axial coherency stresses in MoN/TaN break the cubic symmetry beyond simple tetragonal distortions, leading to a new tetragonal zeta-phase (P4/nmm, #129). Both zeta-MoN and zeta-TaN have lower formation energy than their cubic counterparts. Unlike the cubic TaN, the zeta-TaN is also dynamically stable. The hexagonal alloys are predicted to be extremely hard, though, much less ductile than the cubic polymorphs and superlattices. (C) 2018 Elsevier Ltd. All rights reserved.

Název v anglickém jazyce

Stability and elasticity of metastable solid solutions and superlattices in the MoN-TaN system: First-principles calculations

Popis výsledku anglicky

In order to develop design rules for novel nitride-based coatings, we investigate trends in thermodynamic, structural, elastic, and electronic properties ofMo1-xTaxNsingle-phase alloys together with (MoN)(1-x)/(TaN)(x) superlattices. Our calculations predict that hexagonal Mo1-xTaxN are the overall most stable ones, followed by the disordered cubic solid solutions and superlattices. The disordered cubic systems are energetically clearly favoured over their ordered counterparts. To explain this unexpected phenomenon, we perform an in-depth structural analysis of bond-lengths and angles, revealing that the disordered phase is structurally between the NaCl-type and the hexagonal NiAs-type modifications. Similarly, the bi-axial coherency stresses in MoN/TaN break the cubic symmetry beyond simple tetragonal distortions, leading to a new tetragonal zeta-phase (P4/nmm, #129). Both zeta-MoN and zeta-TaN have lower formation energy than their cubic counterparts. Unlike the cubic TaN, the zeta-TaN is also dynamically stable. The hexagonal alloys are predicted to be extremely hard, though, much less ductile than the cubic polymorphs and superlattices. (C) 2018 Elsevier Ltd. All rights reserved.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Materials and Design

ISSN

0264-1275

e-ISSN

—

Svazek periodika

144

Číslo periodika v rámci svazku

APR

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

13

Strana od-do

310-322

Kód UT WoS článku

000427609400029

EID výsledku v databázi Scopus

2-s2.0-85042302061