Shape memory alloys for biomedical applications Edited by Takayuki Yoneyama and Shuichi Miyazaki CRC Press Boca Raton Boston New York Washington, DC WOODHEAD PUBLISHING LIMITED Cambridge, England
Contributor contact details Preface xi xv Part I Materials 1 Shape memory effect and superelasticity in Ti-Ni alloys 3 S. Miyazaki, University of Tsukuba, Japan and R. L. Sachdeva, OraMetrix, USA 1.1 Introduction 3 1.2 Shape memory effect and superelasticity 4 1.3 Elasticity and superelasticity 7 1.4 Superelasticity in clinical orthodontics 10 1.5 Superelasticity characteristics 13 1.6 Extrapolation factors affecting superelasticity 15 1.7 Conclusions 18 1.8 References 18 2 Mechanical properties of shape memory alloys 20 H. Hosoda and T. INAMURA,Tokyo Institute of Technology, Japan 2.1 Introduction 20 2.2 Stress-strain curves 22 2.3 Stabilization of shape memory effect and superelasticity 27 2.4 Strain-temperature curves 28 2.5 Thermo-mechanical treatment 29 2.6 Multistage transformation 32 2.7 Texture effect 35 2.8 Summary 36 2.9 References 36 v
vi 3 Thermodynamics of the shape memory effect 37 inti-ni alloys Y. LlU, The University of Western Australia, Australia 3.1 Thermal-mechanical coupling of thermoelastic 37 martensitic transformation 3.2 Thermoelasticity of 39 3.3 Equilibrium thermodynamic theory of thermoelastic 42 3.4 Phenomenological thermodynamic theory of thermoelastic 45 3.5 Unified thermodynamic expression of thermoelastic 50 3.6 Thermodynamic expression of transformation temperatures 51 3.7 Transformation heats 55 3.8 Experimental verifications and interpretations 57 3.9 Generalisation of thermodynamic theories of thermoelastic 65 3.10 Summary 67 3.11 References 67 4 Alternative shape memory alloys 69 H. Y. Kim and S. Miyazaki, University of Tsukuba, Japan 4.1 Introduction 69 4.2 Shape memory effect and superelasticity based alloys in Ti-Nb 70 4.3 Effect of interstitial alloying elements on shape memory 75 properties of Ti-based shape memory alloys 4.4 Effect of heat treatment condition on shape memory 77 properties of Ti-based shape memory alloys 4.5 Effect of textures on shape memory properties of 79 Ti-based shape memory alloys 4.6 Ti-Mo based shape memory alloys 81 4.7 Ti-V based shape memory alloys 83 4.8 Conclusions 83 4.9 References 83
vii 5 Fabrication of shape memory alloy parts 86 T. Habu, Furukawa Techno Material Co. Ltd, Japan 5.1 General processing techniques for Ti-Ni alloys 86 5.2 Other machining methods for Ti-Ni alloys 96 5.3 Required properties of Ti-Ni alloys used in medical devices 99 5.4 Prospects 99 5.5 References 99 6 Response of Ti-Ni alloys for dental biomaterials to conditions in the mouth 101 Y. Oshida, Syracuse University and Indiana University, USA and F. Farzin-Nia, Ormco Corporation, USA 6.1 Introduction 101 6.2 Discoloration 102 6.3 Corrosion ofti-ni alloys in various media 103 6.4 Corrosion behavior of Ti-Ni alloys in fluoride-containing solution 104 6.5 Corrosion behavior of Ti-Ni alloys in solution containing chloride ion 105 6.6 CoiTOsion behavior of Ti-Ni alloys in artificial saliva 106 6.7 Corrosion behavior of Ti-Ni alloys in simulated body fluid 107 6.8 Effects of alloying elements in Ti-Ni alloys on corrosion 108 behavior 6.9 Effect of surface modification on corrosion resistance 109 6.10 Release of metal ions and dissolution of Ti-Ni alloys 110 6.11 Allergic reaction, toxicity, and biocompatibility Ti-Ni alloys of 112 6.12 Galvanic corrosion of Ti-Ni alloys 117 6.13 Microbiology-induced corrosion (MIC) of Ti-Ni alloys 118 6.14 Formation of titanium oxides 121 6.15 Air-formed titanium oxides 123 6.16 Passivation of Ti-Ni alloys 125 6.17 Oxidation at elevated temperatures 128 6.18 Crystal structures of titanium oxides 130 6.19 Characterization of oxides 131 6.20 Oxide growth, stability and breakdown 132 6.21 Reaction with hydrogen peroxide 133 6.22 Reaction of titanium with hydrogen 135 6.23 References 137
viii 7 Understanding, predicting and preventing 150 failure of Ti-Ni shape memory alloys used in medical implants K. Gall, Georgia Institute of Technology, USA 7.1 Introduction 150 7.2 Overview of Ti-Ni mechanical failure modes 151 7.3 Inelastic deformation and fracture 152 7.4 Fatigue failure and life analysis 155 7.5 Influence of processing and material structure on 163 material failure 7.6 Influence of manufacturing and surface finish on 164 material failure 7.7 Summary and future trends 165 7.8 Sources of further information and advice 166 7.9 References 167 8 Surface modification of Ti-Ni alloys for 173 biomedical applications M. F. MAITZ, Leibniz Institute of Polymer Research Dresden, Germany 8.1 Introduction 173 8.2 Surface finishing 174 8.3 Surface passivation 176 8.4 Coatings 180 8.5 Sterilization 185 8.6 Summary 186 8.7 References 188 9 Biocompatibility of Nitinol for biomedical 194 applications S. Shabalovskaya, Ames Laboratory, USA and J. Van Humbeeck, Katholieke University Leuven, Belgium 9.1 Introduction 194 9.2 Biomechanical compatibility 195 9.3 Comparative metal toxicity 196 9.4 Patterns of nickel release from Nitinol 197 9.5 Response of cells to Ni release 200 9.6 Thrombogenic potential, platelet adhesion, and protein 205 adsorption
effects ix 9.7 9.8 9.9 9.10 Biological responses In vivo responses Conclusions and future trends References to modified Nitinol surfaces 210 212 225 227 Part II Medical and dental devices 10 Self-expanding Nitinol stents for the treatment 237 of vascular disease D. Stoeckel, A. Pelton and T. Duerig, Nitinol Devices & Components, USA 10.1 Introduction 237 10.2 Nitinol specific device characteristics 238 10.3 Nitinol stent designs 241 10.4 Biocompatibility and corrosion 249 10.5 Fatigue and durability of Nitinol stents 252 10.6 Sources of further information and advice 253 10.7 References 254 11 Orthodontic devices usingti-ni shape 257 memory alloys F. FaRZIn-Nia, Ormco Corporation, USA and T. Yoneyama, Nihon University School of Dentistry, Japan 11.1 Introduction 257 11.2 Wire properties in various stages of orthodontic treatment 258 11.3 Evolution of orthodontic wires 260 11.4 Ti-Ni orthodontic archwires 263 11.5 Ti-Ni alloy wires - of additional elements 281 11.6 Chemical properties in the oral environment 288 11.7 Other orthodontic appliances 289 11.8 11.9 Future trends References 291 292 12 Endodontic instruments for root canal treatment usingti-ni shape memory alloys 297 12.1 12.2 T. Yoneyama, Nihon University School of Dentistry, Japan and C. KOBAYASHI, Tokyo Medical and Dental University, Japan Root canal treatment Stainless-steel instruments 297 298
X 12.3 Ti-Ni alloy instruments 298 12.4 Root canal preparation system with Ti-Ni alloy instruments 303 12.5 Future development of Ti-Ni alloy instruments 303 12.6 References 304 13 Regulation, orthopedic, dental, endovascular and 306 other applications ofti-ni shape memory alloys L'H. YAHIA and F. RAYES, Ecole Polytechnique de Montreal, Canada and A. O. Warrak, University of Montreal, Canada 13.1 Introduction 306 13.2 USA Food and Drug Administration status of 307 Ti-Ni medical devices 13.3 Orthopedic/dental applications of Ti-Ni shape 309 memory alloys 13.4 Endovascular applications or interventions 315 13.5 Other applications of Ti-Ni shape memory alloys 317 13.6 Conclusions 319 13.7 Acknowledgement 320 13.8 References 320 Index 327