Effect of Martensitic Transformation on Local Stresses and Strains at a Notch of Cyclically Loaded Superelastic NiTi Ribbon

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26210%2F17%3APU126234" target="_blank" >RIV/00216305:26210/17:PU126234 - isvavai.cz</a>

Výsledek na webu

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DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Effect of Martensitic Transformation on Local Stresses and Strains at a Notch of Cyclically Loaded Superelastic NiTi Ribbon

Popis výsledku v původním jazyce

Reversible and volume preserving martensitic transformation /MT/ proceeding in shape memory alloys such as NiTi differs from that in steels. Especially in superelastic NiTi largely used in medical devices, the effect of MT on the material response at stress risers and the role of MT in crack nucleation and propagation remain unclear and widely unexplored. Therefore, we studied the effect of MT on the stress and strain fields around a notch of a superelastic NiTi ribbon thus mimicking in a simplified manner mechanics at stress risers of geometrically complex medical devices such as stents or at crack tips of fatigue damaged NiTi elements. We used digital image correlation /DIC/ to track strains around a notch of a NiTi during superelastic. As for the stress evaluation, we used finite element analysis (FEA) coupled with a SMA material model implemented using a user subroutine. In summary, we found that the effect of MT proceeding in NiTi at a constant plateau stress is threefold. First, MT is triggered

Název v anglickém jazyce

Effect of Martensitic Transformation on Local Stresses and Strains at a Notch of Cyclically Loaded Superelastic NiTi Ribbon

Popis výsledku anglicky

Reversible and volume preserving martensitic transformation /MT/ proceeding in shape memory alloys such as NiTi differs from that in steels. Especially in superelastic NiTi largely used in medical devices, the effect of MT on the material response at stress risers and the role of MT in crack nucleation and propagation remain unclear and widely unexplored. Therefore, we studied the effect of MT on the stress and strain fields around a notch of a superelastic NiTi ribbon thus mimicking in a simplified manner mechanics at stress risers of geometrically complex medical devices such as stents or at crack tips of fatigue damaged NiTi elements. We used digital image correlation /DIC/ to track strains around a notch of a NiTi during superelastic. As for the stress evaluation, we used finite element analysis (FEA) coupled with a SMA material model implemented using a user subroutine. In summary, we found that the effect of MT proceeding in NiTi at a constant plateau stress is threefold. First, MT is triggered

Druh

O - Ostatní výsledky

CEP obor

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OECD FORD obor

20306 - Audio engineering, reliability analysis

Projekt

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Návaznosti

S - Specificky vyzkum na vysokych skolach

Rok uplatnění

2017

Kód důvěrnosti údajů

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