Quantum-mechanical study of tensorial elastic and high-temperature thermodynamic properties of grain boundary states in superalloy-phase Ni3Al

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F17%3A00478808" target="_blank" >RIV/68081723:_____/17:00478808 - isvavai.cz</a>

Alternative codes found

RIV/00216224:14740/17:00100291

Result on the web

<a href="http://dx.doi.org/10.1088/1757-899X/219/1/012019" target="_blank" >http://dx.doi.org/10.1088/1757-899X/219/1/012019</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1088/1757-899X/219/1/012019" target="_blank" >10.1088/1757-899X/219/1/012019</a>

Result language

angličtina

Original language name

Quantum-mechanical study of tensorial elastic and high-temperature thermodynamic properties of grain boundary states in superalloy-phase Ni3Al

Original language description

Grain boundaries (GBs), the most important defects in solids and their properties are crucial for many materials properties including (in-)stability. Quantum-mechanical methods can reliably compute properties of GBs and we use them to analyze (tensorial) anisotropic elastic properties of interface states associated with GBs in one of the most important intermetallic compounds for industrial applications, Ni3Al. Selecting the Sigma 5(210) GBs as a case study because of its significant extra volume, we address the mechanical stability of the GB interface states by checking elasticity-based Born stability criteria. One critically important elastic constant, C 55, is found nearly three times smaller at the GB compared with the bulk, contributing thus to the reduction of the mechanical stability of Ni3Al polycrystals. Next, comparing properties of Sigma 5(210) GB state which is fully relaxed with those of a Sigma 5(210) GB state when the supercell dimensions are kept equal to those in the bulk we conclude that lateral relaxations have only marginal impact on the studied properties. Having the complete elastic tensor of Sigma 5(210) GB states we combine Green's-function based homogenization techniques and an approximative approach to the Debye model to compare thermodynamic properties of a perfect Ni3Al bulk and the Sigma 5(210) GB states. In particular, significant reduction of the melting temperature (to 79-81% of the bulk value) is predicted for nanometer-size grains.

Czech name

—

Czech description

—

Type

D - Article in proceedings

CEP classification

—

OECD FORD branch

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

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

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

Publication year

2017

Confidentiality

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

Article name in the collection

38TH RISO INTERNATIONAL SYMPOSIUM ON MATERIALS SCIENCE

ISBN

—

ISSN

1757-8981

e-ISSN

—

Number of pages

11

Pages from-to

—

Publisher name

IOP PUBLISHING LTD

Place of publication

Bristol

Event location

Denmark

Event date

Sep 4, 2017

Type of event by nationality

WRD - Celosvětová akce

UT code for WoS article

000409355600019