Mechanical and Microstructural Properties of Ti-V-Al High Temperature Shape Memory Alloy

Öz

The phase transformation, microstructural and mechanical properties of Ti-15V-2Al high temperature shape memory alloy produced with arc-melting method were investigated by DSC, XRD, SEM and high temperature micro-indenter system. The reverse martensitic transformation As starting and Af finishing temperatures of alloy were obtained to be 195 °C and 285 °C, respectively. In high temperature microindentation analysis, the alloy were subjected to indentation tests under 5000 mN load for three different temperatures (24 °C, 250 °C and 450 °C). The hardness and reduced elastic modulus values of the alloy at room temperature (24 °C ), that is, martensite structure, were found to be higher than the values at 450 °C, that is, austenite structure. The effect of temperature on superelasticity was examined and it was found that the superelasticity value of the alloy was higher at 450 °C compared to its value at 24 °C.

Anahtar Kelimeler

• Shape Memory Alloys
• High Temperature
• Mechanical Properties
• Ti-Based Alloys
• Superelasticity

Ti-V-Al Yüksek Sıcaklık Şekil Hafızalı Alaşımın Mekaniksel ve Mikroyapısal Özellikleri

Öz

Ark eritme yöntemiyle üretilen Ti-15V-2Al yüksek sıcaklıklı şekil hafızalı alaşımın faz dönüşümü, mikroyapısal ve mekaniksel özellikleri DSC, XRD, SEM ve yüksek sıcaklık mikro çentme sistemi ile incelenmiştir. Alaşımın ters martensitik dönüşüm As başlangıç ve Af bitiş sıcaklıkları sırasıyla 195 °C ve 285 °C olarak elde edilmiştir. Yüksek sıcaklık mikro çentme analizlerinde, alaşım üç farklı sıcaklıkta (24°C, 250 °C ve 450 °C) 5000 mN yük altında çentik testlerine tabi tutulmuştur. Alaşımın oda sıcaklığında (24 °C) yani martensit yapısındaki sertlik ve elastik modül değerlerinin, 450 °C'deki yani östenit yapısındaki değerlerden daha yüksek olduğu tespit edilmiştir. Sıcaklığın süperelastisiteye etkisi incelenmiş ve alaşımın 450 °C'deki süperelastisite değerinin daha yüksek olduğu bulunmuştur.

Anahtar Kelimeler

• Şekil Hafızalı Alaşım
• Yüksek Sıcaklık
• Mekaniksel Özellikler
• Ti-Temelli Alaşımlar
• Süperelastisite

Kaynakça

1. G.S. Firstov, J. Van Humbeeck, Y.N. Koval,” High-temperature shape memory alloys, some recent developments,” Mater. Sci. Eng. A, 378, 2–10, 2004.
2. O. Ozbulut, S. Daghash, M. Sherif,” Shape memory alloy cables for structural applications,” J. Mater. Civ. Eng., 28(4), 04015176, 2015.
3. J.V. Humbeeck,” High temperature shape memory alloys,” Engineering Materials and Technology, 121, 4, 1999. J. Ma, I. Karaman and R.D. Noebe,” High temperature shape memory alloys,” International Material Reviews, 55: 5, 257-315, 2010.
4. K.C. Atlı, I. Karaman, R.D. Noebe, A. Garg, Y.I. Chulyakov, I.V. Kireeva, “Shape memory characteristics of Ti49.5Ni25Pd25Sc0.5 high-temperature shape memory alloy after severe plastic deformation,” Acta Mater., 59, 4747–4760, 2011.
5. X.L. Meng, W. Cai, L.M. Wang, Y.F. Zheng, L.C. Zhao, L.M. Zhou, “Microstructure of stress-induced martensite in a Ti–Ni–Hf high temperature shape memory alloy,” Scripta Mater, 45, 1177–1182, 2001.
6. H. Kato, R. Stalmans, J. Van Humbeeck,” Two-way shape memory effect induced by tension training in Cu-13.4Al4.0Ni (mass%) alloy single crystals,” Mater. Trans., 39, 378-386, 1998.
7. X.H, Zheng, J.H. Sui, X. Zhang, Z.Y. Yang, H. B. Wang, X.H. Tian, W. Cai,” Thermal stability and high-temperature shape memory effect of Ti–Ta–Zr alloy,” Scripta Mater, 68, 1008–1011, 2013.
8. K. Otsuka, K.M. Wayman, J. Van Humbeeck, R. Stalmans, “Characteristics of Shape Memory Alloys,” Cambridge University Press., p. 149, Cambridge, 1999.

9. K. Otsuka, X. Ren,” Physical metallurgy of Ti–Ni-based shape memory alloys,” Prog. Mater. Sci., 50, 511–678, 2005.
10. B. Kochar, I. Karaman, J.I. Kim, Y. I. Chumlyakov, J. Sharp,” Thermo-mechanical cyclic response of an ultra fine grained NiTi shape memory alloy,” Acta Mater,56, 3630–3646, 2008.
11. P.J.S. Buenconsejo, H.Y. Kim, H. Hosoda, S. Miyazaki, “Shape Memory Behavior of Ti-Ta and Its Potential as High Temperature Shape Memory Alloy,” Acta Mater., 57, 1068–1077, 2009.
12. S. Ergen, “The effect of indentation temperature and load on mechanical characterization and transformation behavior of high temperature Ti-V-Al-Cu shape memory alloy,” Materials Chemistry and Physics, 268, 124757, 2021.
13. O. Bağ, F. Yılmaz, U. Kölemen, S. Ergen, C. Temiz, O. Uzun, “Transformational, microstructural and superelasticity characteristics of Ti–V–Al high temperature shape memory alloys with Zr addition,” Phys. Scr., 96, 085702, 2021.
14. M. Hiroaki, Y. Hiroshi, F. Damien, M. Eric, C. Akihiko, G. Fumihiko, “Mechanical behaviors of Ti–V– (Al, Sn) alloys with martensite microstructure,” Journal of Alloys and Compounds, 509, 2684–2692, 2011.
15. O. Uzun, N. Basman, C. Alkan, U. Kölemen, F. Yılmaz,” Depth sensing indentation analysis of electrochemically synthesized polythiophene,” Materials Chemistry and Physics, 124, 196–202, 2010.
16. Y. Cui, Y. Li, K. Luo, H. Xu, “Microstructure and shape memory effect of Ti–20Zr–10Nb alloy,” Mat. Sci. Eng. A.,527, 652-656, 2010.
17. E. Takahashi, T. Sakurai, S. Watanabe, N. Masahashi, S. Hanada,” Effect of heat treatment and Sn content on superelasticity in biocompatible TiNbSn alloy,” Mater. Trans. ,43, 12, 2978–2983, 2002.
18. X.H. Zheng, J. H. Su, X. Zhang, X.H. Tian, W. Cai,” Effect of Y addition on the martensitic transformation and shape memory effect of Ti-Ta high-temperature shape memory alloy,” Journal of Alloys and Compounds, 539, 144- 147, 2012.
19. O. Bağ, S. Ergen, F. Yılmaz, U. Kölemen,” Influence of Al content on transformation temperature and activation energy of Ti–V–Al high temperature shape memory alloys,” Solid State Communications, 323, 114104, 2021.
20. F. Yılmaz, O. Uzun, U. Kölemen, M.F. Kılıcaslan, N. Basman, S. Ergen, K. Ozturk, E. Yanmaz,” Nanoindentation study on Gd-deposited YBaCuO superconductor,” Bull. Mater. Sci., 36, 7, 1139–1145, 2013.
21. O. Uzun, F. Yılmaz, U. Kölemen, N. Basman,” Sb effect on micro structural and mechanical properties of rapidly solidified Al–12Si alloy,” Journal of Alloys and Compounds, 509, 21–26, 2011.
22. F. Khaleghi, M. Tajally, E. Emadoddin and M. Mohri,” The investigation of the mechanical properties of graded hightemperatureshape memory Ti-Ni-Pd alloy,” J. Alloys Compd., 787, 882–92, 2019.
23. X. Yi, B. Sun, W. Gao, X. Meng, Z. Gao, W. Cai and L. Zhao, “Microstructure evolution and superelasticity behaviorofTi-Ni-Hfshapememory alloy composite with multi-scale and heterogeneous reinforcements,” Journal of Materials Science & Technology, 42, 113–21, 2020.