Investigation of the Effect of Heat Treatments at Different Temperatures on the Crystal Structure of Titanium-Nickel Films

Öz

Titanium-nickel films have an increasing interest and an increasing potential use in recent years thanks to their shape memory properties and super elasticity properties. Titanium-nickel films grown by magnetron sputtering method have amorphous internal structure. In order to give shape memory and super elastic properties, these films are heat treated and the internal structure is transformed into crystal phase. In this study, titanium-nickel films grown by magnetron sputtering method were subjected to heat treatment in an atmosphere controlled tube furnace at six different temperature values. Phase changes of the films were determined by XRD analysis, micro structures were observed by SEM images and phase transformation temperatures determined by DSC analysis. As a result of the study, it was determined that different heat treatment temperatures greatly changed the internal structure. According to the results, it was determined that the heat treatment at 550 ° C was suitable for TiNi applications at room temperature.

Anahtar Kelimeler

• titanium-nickel film
• shape-memory
• phase transformation
• heat treatment

Farklı Sıcaklıklarda Yapılan Isıl İşlemlerin Titanyum-Nikel Filmlerin Kristal Yapısına Etkisinin Araştırılması

Öz

Titanyum-nikel filmler sahip oldukları şekil hafıza özelliği ve süper elastiklik özellikleri sayesinde son yıllarda giderek artan bir ilgiye ve artan bir potansiyel kullanım alanına sahiptir. Magnetron sıçratma yöntemiyle büyütülen titanyum-nikel filmler amorf iç yapıya sahiptir. Şekil hafıza ve süper elastik özelliklerinin kazandırılması için bu filmlere ısıl işlem yapılmakta ve iç yapı kristal faza dönüştürülmektedir. Bu çalışmada magnetron sıçratma yöntemi ile büyütülen titanyum-nikel filmler altı farklı sıcaklık değerinde atmosfer kontrollü tüp fırın içerisinde ısıl işleme tabi tutulmuştur. Filmlerin faz değişimleri XRD analizleri ile, iç yapıları SEM görüntüleri ile, faz dönüşüm sıcaklıkları DSC analizleri ile belirlemiştir. Çalışma sonucu farklı ısıl işlem sıcaklıklarının iç yapıyı büyük oranda değiştirdiği belirlenmiştir. Elde edilen sonuçlara göre 550°C de yapılan ısıl işlemin oda sıcaklığındaki uygulamalar için daha uygun olduğu tespit edilmiştir.

Anahtar Kelimeler

• titanyum-nikel film
• şekil hafıza
• faz dönüşüm
• ısıl işlem

Kaynakça

1. Chen, Peter, and Jyh Ming Ting, 2001. Characteristics of TiNi Alloy Thin Films. Thin Solid Film, 398: 597–601.
2. Chu, J P, Y W Lai, T N Lin, and S F Wang, 2000. Deposition and Characterization of TiNi-Base Thin Films by Sputtering. Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 277: 11–17.
3. Cicek, Hikmet, Ihsan Efeoglu, Yaşar Totik, Kadri Vefa Ezirmik, and Ersin Arslan, 2015. A Low Temperature In-Situ Crystalline TiNi Shape Memory Thin Film Deposited by Magnetron Sputtering. Surface and Coatings Technology, 284: 90–93.
4. Dilibal, S, 2016. The effect of long-term heat treatment on the thermomechanical behavior of NiTi shape memory alloys in defense and aerospace applications. Defense Science Journal, 15(2), 1-23.
5. Fu, Yongqing, and Hejun Du, 2003. Effects of Film Composition and Annealing on Residual Stress Evolution for Shape Memory TiNi Film. Materials Science and Engineering A, 342: 236-244.
6. Fu, Yongqing, Hejun Du, Weimin Huang, Sam Zhang, and Min Hu, 2004. TiNi-Based Thin Films in MEMS Applications: A Review. Sensors and Actuators, A: Physical, 112: 395-408.
7. Kahn, H., M. A. Huff, and A. H. Heuer, 1998. The TiNi Shape-Memory Alloy and Its Applications for MEMS. Journal of Micromechanics and Microengineering, 8:1-7.
8. Kim, Seong Woong, Yeong Min Jeon, Chan Hee Park, Jeoung Han Kim, Dong Ho Kim, and Jong Taek Yeom, 2013. Martensitic Phase Transformation of TiNi Thin Films Fabricated by Co-Sputtering Deposition. Journal of Alloys and Compounds, 580: 5–9.

9. Li, D.Y, 2000. Exploration of TiNi Shape Memory Alloy for Potential Application in a New Area : Tribological Engineering. Smart Materials and Structures, 9: 717–726.
10. Li, Zhenhua, Xianhua Cheng, and Qianqian Shangguan, 2005. Effects of Heat Treatment and ECAE Process on Transformation Behaviors of TiNi Shape Memory Alloy. Materials Letters, 59:705-709.
11. Miyazaki, Shuichi, Yong Qing Fu, and Wei Min Huang, 2009. Thin Film Shape Memory Alloys: Fundamentals and Device Applications. Thin Film Shape Memory Alloys: Fundamentals and Device Applications. Cambridge.
12. Surbled, Patrick, Catherine Clerc, Bruno Le Pioufle, Manabu Ataka, and Hiroyuki Fujita, 2001. Effect of the Composition and Thermal Annealing on the Transformation Temperatures of Sputtered TiNi Shape Memory Alloy Thin Films. Thin Solid Films ,401: 52–59.
13. Tang, Guanghai, Dongya Zhang, Junfeng Zhang, Ping Lin, and Guangneng Dong, 2014. Self-Recovery of Worn Surface of TiNi Shape Memory Alloy. Applied Surface Science, 321: 371-377.
14. Zhang, L, C Y Xie, and J S Wu, 2007. Effect of Annealing Temperature on Surface Morphology and Mechanical Properties of Sputter-Deposited Ti-Ni Thin Films. Journal of Alloys and Compounds, 427: 238–43.