Temperature and microstructure dependence of localized tensile deformation of superelastic NiTi wires

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389005%3A_____%2F19%3A00504698" target="_blank" >RIV/61389005:_____/19:00504698 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/68378271:_____/19:00517457 RIV/68407700:21340/19:00337225

Výsledek na webu

<a href="https://doi.org/10.1016/j.matdes.2019.107797" target="_blank" >https://doi.org/10.1016/j.matdes.2019.107797</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.matdes.2019.107797" target="_blank" >10.1016/j.matdes.2019.107797</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Temperature and microstructure dependence of localized tensile deformation of superelastic NiTi wires

Popis výsledku v původním jazyce

Superelastic NiTi wires possessing wide range of microstructures were deformed in tensile tests up to the end of the stress plateau in a wide temperature range -20 -200 degrees C. unloaded and stress free heated to similar to 200 degrees C. The recoverability of upper plateau strains was evaluated in dependence on the test temperature and wire microstructure. At low temperatures below 20 degrees C, the upper plateau strains are fully recoverable upon unloading and heating. With increasing test temperature, however, the recoverability of upper plateau strains becomes gradually lost. Unusually long upper plateaus (10-17%) were observed at test temperatures, at which the upper plateau stress approached the yield stress for plastic deformation of martensite. The volume fraction of the martensite phase at the end of the stress plateau (evaluated by in-situ electric resistance and synchrotron x-ray diffraction) decreases with increasing test temperature in the range where the long plateaus were observed. TEM analysis revealed high density of {114) austenite twins in wires deformed in this temperature range. These observations are rationalized by gradual increase of the activity of the stress-induced B2 -> B19' - B2(T) martensitic transformation into twinned austenite and plastic deformation by dislocation slip with increasing test temperature.

Název v anglickém jazyce

Temperature and microstructure dependence of localized tensile deformation of superelastic NiTi wires

Popis výsledku anglicky

Superelastic NiTi wires possessing wide range of microstructures were deformed in tensile tests up to the end of the stress plateau in a wide temperature range -20 -200 degrees C. unloaded and stress free heated to similar to 200 degrees C. The recoverability of upper plateau strains was evaluated in dependence on the test temperature and wire microstructure. At low temperatures below 20 degrees C, the upper plateau strains are fully recoverable upon unloading and heating. With increasing test temperature, however, the recoverability of upper plateau strains becomes gradually lost. Unusually long upper plateaus (10-17%) were observed at test temperatures, at which the upper plateau stress approached the yield stress for plastic deformation of martensite. The volume fraction of the martensite phase at the end of the stress plateau (evaluated by in-situ electric resistance and synchrotron x-ray diffraction) decreases with increasing test temperature in the range where the long plateaus were observed. TEM analysis revealed high density of {114) austenite twins in wires deformed in this temperature range. These observations are rationalized by gradual increase of the activity of the stress-induced B2 -> B19' - B2(T) martensitic transformation into twinned austenite and plastic deformation by dislocation slip with increasing test temperature.

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

2019

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

174

Číslo periodika v rámci svazku

7

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

21

Strana od-do

107797

Kód UT WoS článku

000466951500013

EID výsledku v databázi Scopus

2-s2.0-85062748549