SavedAdd your journal

Journals / Yenilikçi Mühendislik ve Doğa Bilimleri / 2024 / Volume: 4 Issue: 2

Effect of heat treatment conditions on the phase transformation characteristics of nitinol

Isıl işlem koşullarının nitinolün faz dönüşüm karakteristikleri üzerindeki etkisi

Levent Öncel(SİNOP ÜNİVERSİTESİ, MÜHENDİSLİK VE MİMARLIK FAKÜLTESİ)0000-0002-6018-8741
Mahmut Açma(İSTANBUL TEKNİK ÜNİVERSİTESİ)0000-0003-1315-2030
Pages
—
Publication Date
2024-07-31
🏛️Bibliographic metadata and full text access for this article are provided via DergiPark.
DergiPark Record ↗
✨

AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

Experimental studies showed that the austenite finish (Af) temperature of all nitinol wire samples was below 37 °C, and they will exhibit superelasticity in the human body.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:Nitinol is the most widely used shape memory alloy in medical applications.
📊
Key Findings & Data:Nickel-rich nitinol wires containing 50.6% nickel with a diameter of 120 μm were used in the experimental studies.
💡
Conclusion & Impact:Experimental studies showed that the austenite finish (Af) temperature of all nitinol wire samples was below 37 °C, and they will exhibit superelasticity in the human body.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:nitinol · superelasticity · shape memory alloy

Abstract

Nitinol is the most widely used shape memory alloy in medical applications. In this study, the effect of different heat treatment conditions on the phase transformation characteristics of medical-grade nitinol was investigated. Nickel-rich nitinol wires containing 50.6% nickel with a diameter of 120 μm were used in the experimental studies. The nitinol wires were heat treated for 10 minutes at heat treatment temperatures between 540 and 570 °C. Then, nitinol wires were heat treated at a heat treatment temperature of 550 °C between 8 and 14 minutes. The austenitic and martensitic transition temperatures of these samples were measured using differential scanning calorimetry (DSC). In the experiments with 10 minutes of heat treatment time, transition temperatures decreased, and hysteresis increased with the increase in heat treatment temperature. This is related to the amount of precipitates in the structure. In the experiments carried out at 550 °C, transition temperatures decreased, and hysteresis increased with increasing heat treatment time. Experimental studies showed that the austenite finish (Af) temperature of all nitinol wire samples was below 37 °C, and they will exhibit superelasticity in the human body.

Özet

Nitinol medikal uygulamalarda en yaygın olarak kullanılan şekil hafızalı alaşımdır. Bu çalışmada farklı ısıl işlem koşullarının medikal-sınıf nitinolün faz dönüşüm karakteristikleri üzerindeki etkisi araştırılmıştır. Yapılan deneysel çalışmalarda 120 μm çapında ve %50,6 nikel içeren, nikel-zengin nitinol teller kullanılmıştır. Nitinol teller 540 °C ile 570 °C arasındaki ısıl işlem sıcaklıklarında 10 dakika boyunca ısıl işleme tabi tutuldu. Ardından, nitinol teller 550 °C ısıl işlem sıcaklığında 8 dakika ile 14 dakika arasında ısıl işleme tabi tutuldu. Bu numunelerin östenitik ve martenzitik geçiş sıcaklıkları diferansiyel taramalı kalorimetre (DSC) kullanılarak ölçüldü. 10 dakika boyunca ısıl işleme tabi tutulan numunelerde, ısıl işlem sıcaklığının artmasıyla faz geçiş sıcaklıklarında düşüş gerçekleşmiş, histerezis ise artış göstermiştir. Bu durum mikroyapıdaki çökeltilerin miktarı ile ilişkilidir. 550 °C’de ısıl işleme tabi tutulan numunelerde, ısıl işlem süresinin artışı ile birlikte faz geçiş sıcaklıkları düşmüş ve histerezis artış göstermiştir. Deneysel çalışmalar, kullanılan bütün ısıl işlem koşullarında nitinol tellerin östenit bitiş (Af) sıcaklığının 37 °C’nin altında olduğunu ve vücut içinde süperlastisite göstereceğini ortaya koymuştur.

🔖

Cite This Article

Öncel, L., Açma, M. (2024). Effect of heat treatment conditions on the phase transformation characteristics of nitinol. Yenilikçi Mühendislik ve Doğa Bilimleri, Volume: 4 Issue: 2. https://doi.org/10.61112/jiens.1484623

📄 Full Text PDF Viewer

📄

PDF görüntüleyici hazırlanıyor...

References (17)

  1. Machado LG, Lagoudas DC (2008) Modeling of SMAs. Springer US, Boston
  2. Buehler WJ, Gilfrich J V, Wiley RC (1963) Effect of low-temperature phase changes on the mechanical properties of alloys near composition TiNi. J Appl Phys 34(5):1475-1477. https://doi.org/10.1063/1.1729603
  3. Ziółkowski A (2015) Pseudoelasticity of Shape Memory Alloys. Elsevier, Oxford
  4. Donkersloot HC, Van Vucht JHN (1970) Martensitic transformations in gold-titanium, palladium-titanium and platinum-titanium alloys near the equiatomic composition. J Less Common Met 20(2):83-91. https://doi.org/10.1016/0022-5088(70)90092-5
  5. Melton KN, Mercier O (1978) Deformation behavior of NiTi-based alloys. Metall Trans A 9(10):1487-1488. https://doi.org/10.1007/BF02661822
  6. Sato A, Chishima E, Soma K, Mori T (1982) Shape memory effect in γ⇄ε transformation in Fe-30Mn-1Si alloy single crystals. Acta Metall 30(6):1177-1183. https://doi.org/10.1016/0001-6160(82)90011-6
  7. Maki T, Kobayashi K, Minato M, Tamura I (1984) Thermoelastic martensite in an ausaged FeNiTiCo alloy. Scr Metall 18(10):1105-1109. https://doi.org/10.1016/0036-9748(84)90187-X
  8. Miyazaki S, Ohmi Y, Otsuka K, Suzuki Y (1982) Characteristics of Deformation and Transformation Pseudoelasticity in Ti-Ni Alloys. J Phys (Paris), Colloq. 43(12):C4255. https://doi.org/10.1051/jphyscol:1982434
  9. Yamauchi K, Ohkata I, Tsuchiya K, Miyazaki S (2011) Shape Memory and Superelastic Alloys. Woodhead Publishing Limited, Cambridge
  10. Es-Souni M, Es-Souni M, Fischer-Brandies H (2005) Assessing the biocompatibility of NiTi shape memory alloys used for medical applications. Anal Bioanal Chem 381(3):557-567. https://doi.org/10.1007/s00216-004-2888-3
  11. Dasgupta R (2014) A look into Cu-based shape memory alloys: Present scenario and future prospects. J Mater Res 29(16):1681-1698. https://doi.org/10.1557/jmr.2014.189
  12. Otsuka K, Kakeshita T (2002) Science and technology of shape-memory alloys: New developments. MRS Bull 27(2):91-100. https://doi.org/10.1557/mrs2002.43
  13. Duerig TW, Melton KN (1990) Engineering Aspects of Shape Memory Alloys. Elsevier, London
  14. Ōtsuka K, Wayman CM (1998) Shape Memory Materials. Cambridge University Press, Cambridge
  15. Lexcellent C (2013) Shape-Memory Alloys Handbook. Hoboken, John Wiley & Sons, Inc, New Jersey
  16. Yoneyama T, Miyazaki S (2008) Shape Memory Alloys for Biomedical Applications. Woodhead Publishing, Cambridge
  17. Otsuka K, Ren X (2005) Physical metallurgy of Ti-Ni-based shape memory alloys. Prog Mater Sci 50(5):511-678. https://doi.org/10.1016/j.pmatsci.2004.10.001