Ömer ÇAKMAK, Mehmet KAYA

Akıllı Malzeme Şekil Hafızalı Alaşımların Termodinamiği

Akıllı malzemeler, dışarıdan uygulanan etkiler karşısında istenilen tepkileri anlık ve aralıksız bir şekilde yerine getirebilen malzemelerdir. Akıllı malzemelerin bir türü olan Şekil Hafızalı Alaşımlar (ŞHA), uygun ısıl veya mekanik etkilere maruz kaldıklarında önceki şekil ya da boyutuna dönebilme özelliğine sahiptirler. ŞHA’daki şekil değişimi mikro ve makro yapılar arasındaki faz dönüşümü ile ilgilidir. Bu faz dönüşümleri malzemenin yapısında meydana gelen ısı ve enerji değişiminden kaynaklanmakta ve termodinamik yasalara uymaktadır. Şekil hafızalı alaşımların daha iyi anlaşılması için şekil hafıza olayının temelini oluşturan martensitik faz dönüşümünün termodinamiğinin bilinmesi gerekmektedir.

Anahtar Kelimeler:

Şekil hafızalı alaşımlar, Martensitik faz dönüşümü, Termodinamik, Akıllı malzeme

Thermodynamics of Smart Materiel Shape Memory Alloys

Smart materials can fulfill the desired reactions instantaneously and continuously in response to external applied effects. Shape Memory Alloys (SMA), a type of smart materials, have the ability to return to their previous shapes or sizes when exposed to appropriate thermal or mechanical influences. The shape change of SMA is related to the phase transformation between micro and macro structures. These phase transformations conform thermodynamic laws and are caused by heat and energy changes occurring in the structure of the material. For a better understanding of shape memory alloys, the thermodynamics of the martensitic phase transformation, which is the basis of the shape memory phenomenon, must be known.

Keywords:

Shape memory alloys, Martensitic phase transformation, Thermodynamics, Smart material,

PDF

___

[1] Kaya, M., Toz metalürjisi ile üretilen şekil hatırlamalı alaşımların metalürjik ve mekanik karakteristiklerinin incelenmesi, , Fırat üniversitesi, Ben Bilimleri Enstitüsü, Doktora tezi, 127s,Elazığ, 2008
[2] Kaya M., Çakmak Ö., Saygılı T., Atlı K., Şekil hafızalı alaşımlarda martensitik faz dönüşümü ve şekil hafıza mekanizması, Selçuk Üniversitesi, Teknik-online dergi 15: 157-172, 2016
[3] Ryhanen, J., Bicompatibility evaluation of nichel titanium shape memory metal alloy, Oulu university library, PhD. Thesis, 155p, Oulu, 1999
[4] Eskil, M., Seval, E., Akis, A.Ç., Şekil hatırlamalı CoNiAl alaşımlarının kristalografik özellikleri, Erciyes Üniversitesi, Fen Bilimleri Enstitüsü Dergisi, 30, 19-28, 2014
[5] Jani J.M., Leary, M., Subic, A., Gibson, M.A., A review of shape memory alloy research, applications and opportunities, Materials and Design 56: 1078-113, 2014
[6] Arghavani J., Thermo-mechanical behavior of shape memory alloys under multiaxial loading: constitutive modeling and numerical imlementation at small and finite strains, Sharif University of Technology, Mechanical Engineering Department, PhD Thesis, 186p, 2010
[7] Otsuka, K., Ren, X., Physical metallurgy of Ti–Ni-based shape memory alloys, Progress in materials science 50, 511–678, 2005
[8] Nastasi, M., Mayer, J.W., Thermodynamics and kinetics of phase transformations induced by ion irradiation, Materials science reports 6, 3 1-51, 1991
[9] Joseph M. Powers, Lecture notes on thermodynamics, Department of aerospace and mechanical engineering, University of notre dame notre dame, Indiana 46556-5637 USA Updated 29 June 2016
[10] Porter, D.A. and Easterling, K.E., Phase transformations in metals and alloys, Second Edition, Chapman & Hall, T.J. Press (Padstow) Ltd., UK. 107-117, 1992
[11] Max Planck, Treatise on thermodynamics, Fifth edition, Dover publications, INC, Berlin, 132, 1917
[12] John Denker, https://www.av8n.com/physics/thermo-laws.pdf
[13] Aydın, S., Metalurji ve malzeme mühendisleri için termodinamik, İstanbul: Literatür yayınları; 78, 2014
[14] Mihalcz, I., Fundamental characteristics and design method for nickel-titanium shape memory alloy, Periodica polytechnic Ser. Mech. Eng. 45, 1, 75-86, 2001
[15] Santiago Anadon J.R., Large force shape memory alloy linear actuator, University of Florida, Master Thesis, 122p, 2002
[16] Daniel J. Fernandes, Rafael V. Peres, Alvaro M. Mendes, and Carlos N. Elias, Understanding the shape-memory alloys used in orthodontics, International scholarly research network, 1-6, 2011
[17] Nishiyama, Z., Martensitic transformation, Academic Press, NEW YORK, 123-136, 1978
[18] Kazanç, S., Zor etkili difüzyonsuz faz dönüşümlerinin bilgisayar benzetimi ile incelenmesi, Fırat Üniversitesi Fen Bilimleri Enstitüsü, Yüksek Lisans Tezi, 135s, Elazığ. 2000
[19] Ergen S., Hızlı katılaştırılmış şekil hafızalı Cu-Al-Be alaşımının üretimi ve karakterizasyonu, Gaziosmanpaşa Üniversitesi, Fen Bilimleri Enstitüsü, Doktora tezi, 116, 2014
[20] Khaled M.M., A study of iron based alloys by positron annihilation spectroscopy, Ghent University, PhD Thesis, 143p, Mei 2009
[21] Falvo, A., Thermomechanical characterization of Nickel-Titanium Shape Memory Alloys, Department of mechanical engineering, 2008
[22] Otsuka, K. and Ren, X., Recent development in the research of shape memory alloys, Intermetallics 7: 511-528, 1999
[23] Schiller, E.H., Heat engine driven by shape memory alloys: Prototyping and design, Thesis submitted to the Faculty of Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for a degree of master of science in mechanical engineering, 122p, Virginia, 2002
[24] Olson G.B. and Owen W.S., Martensite, ASM international, The materials information society, USA 1992
[25] Kauffmann-Weiss, S., Kauffmann, A., Niemann, R., Freudenberger, J., Schultz, L., and Fahler, S., Twinning phenomena along and beyond the Bain Path, Metals, 4: 319-336, 2013
[26] Bernal L.I.B., Cyclic Behavior of Superelastic Nickel-Titanium and nickel titanium-chromium shape memory alloys, Georgia Institute of Technology, Master Thesis, 142p, Georgia, 2004
[27] Liu, Yinong, Liu, Yong and Humbeeck, Jan Van, Two-way shape memory effect developed by martensite deformation in NiTi, Acta mater, 47-1: 199-209, 1999
[28] Simon, A.A., Shape memory response and microstructural evolution of a severe plastically deformed high temperature shape memory alloy (NiTiHf), Submitted to the office of graduate studies of Texas A&M University in partial fulfillment of the requirements for the degree of master of science, 134p, Texas, 2004
[29] Brian E., Structure and thermomechanical behavior of NiTiPt shape memory alloy wires, Georgia Institute of Technology, Master Degree, 133p, Georgia, 2009
[30] Otsuka, K., Saxena, A., Deng, J., and Ren, X., Mechanism of the shape memory effect in martensitic alloys: an assessment, Philosophical Magazine, 91, 36, 4514–4535, 2011
[31] Otsuka, K., Wayman, C.M., Shape memory materials, Cambridge university press, 213p, 1998
[32] Asim Rahimatpure, Smart memory alloys, Proc. of Int. Conf. on Advances in Mechanical Engineering 1-3, 2012
[33] Kakeshita, T., Saburi, T., Shımızu, K., Effect of magnetic field and hydrostatic pressure on martensitic transformation in some memory alloys, Mat. Res. Soc. Symp. Proc., Materials Research Society 459: 269-279. 1997
[34] Marukawa, K., Tsuchıya, K. and Arai, I., Short range ordering and stabilization of the martensite phase in copper alloys, J. Phys. IV. 1995
[35] Muller, I., and Seelecke, S., Thermodynamic aspects of shape memory alloys, Mathematical and computer modelling 34, 1307-1355, 2001
[36] Yamauchi, K., Ohkata, I., Tsuchiya, K., Miyazaki, S., Shape memory and superelastic alloys, Oxford, Cambridge, Philadephia, New Delhi: Woodhead publishing, 153p, 2011