TEM observation of twins in surface grains of superelastic NiTi wire after cyclic loading

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F20%3A00538888" target="_blank" >RIV/68378271:_____/20:00538888 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/00216208:11320/20:10422440

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0921509320303543" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0921509320303543</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.msea.2020.139271" target="_blank" >10.1016/j.msea.2020.139271</a>

Jazyk výsledku

angličtina

Název v původním jazyce

TEM observation of twins in surface grains of superelastic NiTi wire after cyclic loading

Popis výsledku v původním jazyce

Since the surface dominates fatigue of medical grade NiTi wire by yet unexplained causes, for comparison, we carried out a TEM observation of surface grains, both after one thousand superelastic cycles and on the unloaded wire. Crystallographic defects consisting of aggregates of austenite twins stacked in the bands were observed after cycling deformation. The nuclei of aggregates are already present in an unloaded wire that originates from cold drawing or heat treatment. Severe plastic deformation induced by a stress increasing in the surface during a cyclic phase transformation enables an accumulation of these aggregates into bands at inclined angle of 55° to the wire axis corresponding to the spreading of diffused martensite band front paths during their propagation. An unrecovered strain, suppression of transformation and acceleration of crack propagation can be expected while the aggregates grow.

Název v anglickém jazyce

TEM observation of twins in surface grains of superelastic NiTi wire after cyclic loading

Popis výsledku anglicky

Since the surface dominates fatigue of medical grade NiTi wire by yet unexplained causes, for comparison, we carried out a TEM observation of surface grains, both after one thousand superelastic cycles and on the unloaded wire. Crystallographic defects consisting of aggregates of austenite twins stacked in the bands were observed after cycling deformation. The nuclei of aggregates are already present in an unloaded wire that originates from cold drawing or heat treatment. Severe plastic deformation induced by a stress increasing in the surface during a cyclic phase transformation enables an accumulation of these aggregates into bands at inclined angle of 55° to the wire axis corresponding to the spreading of diffused martensite band front paths during their propagation. An unrecovered strain, suppression of transformation and acceleration of crack propagation can be expected while the aggregates grow.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10306 - Optics (including laser optics and quantum optics)

Projekt

<a href="/cs/project/EF15_006%2F0000674" target="_blank" >EF15_006/0000674: HiLASE Centre of Excellence</a><br>

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

Materials Science and Engineering A-Structural materials

ISSN

0921-5093

e-ISSN

—

Svazek periodika

782

Číslo periodika v rámci svazku

Apr

Stát vydavatele periodika

CH - Švýcarská konfederace

Počet stran výsledku

6

Strana od-do

1-6

Kód UT WoS článku

000525797900019

EID výsledku v databázi Scopus

2-s2.0-85082175789