How Nanoscale Dislocation Reactions Govern Low- Temperature and High-Stress Creep of Ni-Base Single Crystal Superalloys

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081723%3A_____%2F20%3A00534080" target="_blank" >RIV/68081723:_____/20:00534080 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.mdpi.com/2073-4352/10/2/134" target="_blank" >https://www.mdpi.com/2073-4352/10/2/134</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.3390/cryst10020134" target="_blank" >10.3390/cryst10020134</a>

Jazyk výsledku

angličtina

Název v původním jazyce

How Nanoscale Dislocation Reactions Govern Low- Temperature and High-Stress Creep of Ni-Base Single Crystal Superalloys

Popis výsledku v původním jazyce

The present work investigates gamma-channel dislocation reactions, which govern low-temperature (T = 750 degrees C) and high-stress (resolved shear stress: 300 MPa) creep of Ni-base single crystal superalloys (SX). It is well known that two dislocation families with different b-vectors are required to form planar faults, which can shear the ordered gamma'-phase. However, so far, no direct mechanical and microstructural evidence has been presented which clearly proves the importance of these reactions. In the mechanical part of the present work, we perform shear creep tests and we compare the deformation behavior of two macroscopic crystallographic shear systems [011 over bar ](111) and [112 over bar ](111). These two shear systems share the same glide plane but differ in loading direction. The [112 over bar ](111) shear system, where the two dislocation families required to form a planar fault ribbon experience the same resolved shear stresses, deforms significantly faster than the [011 over bar ](111) shear system, where only one of the two required dislocation families is strongly promoted. Diffraction contrast transmission electron microscopy (TEM) analysis identifies the dislocation reactions, which rationalize this macroscopic behavior.

Název v anglickém jazyce

How Nanoscale Dislocation Reactions Govern Low- Temperature and High-Stress Creep of Ni-Base Single Crystal Superalloys

Popis výsledku anglicky

The present work investigates gamma-channel dislocation reactions, which govern low-temperature (T = 750 degrees C) and high-stress (resolved shear stress: 300 MPa) creep of Ni-base single crystal superalloys (SX). It is well known that two dislocation families with different b-vectors are required to form planar faults, which can shear the ordered gamma'-phase. However, so far, no direct mechanical and microstructural evidence has been presented which clearly proves the importance of these reactions. In the mechanical part of the present work, we perform shear creep tests and we compare the deformation behavior of two macroscopic crystallographic shear systems [011 over bar ](111) and [112 over bar ](111). These two shear systems share the same glide plane but differ in loading direction. The [112 over bar ](111) shear system, where the two dislocation families required to form a planar fault ribbon experience the same resolved shear stresses, deforms significantly faster than the [011 over bar ](111) shear system, where only one of the two required dislocation families is strongly promoted. Diffraction contrast transmission electron microscopy (TEM) analysis identifies the dislocation reactions, which rationalize this macroscopic behavior.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

20501 - Materials engineering

Projekt

—

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2020

Kód důvěrnosti údajů

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

Název periodika

Crystals

ISSN

2073-4352

e-ISSN

—

Svazek periodika

10

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

15

Strana od-do

134

Kód UT WoS článku

000519704700002

EID výsledku v databázi Scopus

2-s2.0-85081281283