5 INFLUENCE OF ALLOYING ELEMENTS AND AGING TREATMENT …eprints.utm.my/id/eprint/77887/1/SafaaNajahSaudPFKM2014.pdf · v ABSTRACT Nickel-Titanium (Ni Ti) shape memory alloys (SMAs)

5

INFLUENCE OF ALLOYING ELEMENTS AND AGING TREATMENT ON THE

PHASE TRANSFORMATION AND SHAPE MEMORY BEHAVIOR OF

Cu-Al-Ni SHAPE MEMORY ALLOYS

SAFAA NAJAH SAUD

A thesis submitted in fulfilment of the

requirements for the award of the degree of

Doctor of Philosophy (Mechanical Engineering)

Faculty of Mechanical Engineering

Universiti Teknologi Malaysia

NOVMENBER 2014

Safaaeng

Stamp

iii

To:

My beloved family

iv

ACKNOWLEDGEMENT

First of all I would like to thank Allah for this valuable time given, where I

had the chance to understand about His wonders on materials.

I am deeply grateful to my supervisor, Prof Dr. Esah Hamzah for her

guidance, patience and support. I have been extremely lucky to have a supervisor

who cared so much about my work, and who responded to my questions and queries

so promptly. I would like to thank my co-supervisor, Dr. Tuty Asma Abu Bakar for

her useful advices and encouragement. Without their valuable advice, kind

encouragement and trust, I would not have reached this point.

I would like to acknowledge the Malaysian Ministry of Higher Education

(MOHE) and Universiti Teknologi Malaysia for providing the financial support and

facilities for this research under Grant No. R.J130000.7824.4F150. I am also

grateful for the Universiti Teknologi Malaysia for their support by international

doctorate fellowship (IDF) during this research.

My thanks are also due to the staff, faculty members, and technicians of the

Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, who contributed

to my research.

I am most grateful to my family, my dearest Raheleh and close friends for

their infinite support, patience and encouragements during these years.

v

ABSTRACT

Nickel-Titanium (Ni-Ti) shape memory alloys (SMAs) have been used in many

engineering and medical applications. However, their use is limited, due to their low

transformation temperatures, difficulties in processing and high cost of the raw materials. As

an alternative material to Ni-Ti alloys, copper-based alloys are successfully being used.

Among copper-based SMAs, Cu-Al-Ni alloys are used in a wide range of applications,

particularly if high temperatures are required. However, Cu-Al-Ni SMAs also have

limitations such as very low ductility and low shape recovery strain. Therefore, this research

aims to enhance the ductility and shape memory effect of Cu-Ni-Al by alloying additions

and aging heat treatment. The base metal, Cu-Al-Ni, was cast without and with different

amounts of the fourth alloying elements, namely, titanium (Ti), manganese (Mn) and cobalt

(Co). The modified and unmodified alloys were homogenized and aged at 373 K, 423 K and

523 K for 24 and 48 hours. Phase transformation and microstructural changes were

characterized using techniques such as optical microscopy, field emission scanning electron

microscopy (FESEM), energy dispersive spectrometry (EDS), differential scanning

calorimetry (DSC), x-ray diffractometry (XRD) and transmission electron microscopy

(TEM). The tensile properties and hardness were determined using a universal Instron

tensile machine and Vicker‟s hardness test machine, respectively. The shape memory test

was performed using a specially designed tensile machine equipped with a heating tape. The

results revealed that the alloying elements and aging treatment were found to control the

phase morphology, orientations and grain size along with the formation of precipitates,

thereby improving the shape memory characteristics, ductility and hardness. The volume

fraction, size and distribution of the precipitates are mainly dependent on the type and

amount of alloying element as well as the condition of aging treatment. The Cu-Al-Ni with

the addition of 0.76 wt. % Ti and age treated showed complete recovery after the shape

memory test. This may be attributed to the high volume of X-phase precipitates and grain

refinement that led to the restricted mobility of martensite variant interfaces and dislocations.

It was found that the alloy with 1.14 wt. % of Co gave the best overall improvement in terms

of the transformation temperatures, ductility and shape memory recovery. These

improvements were mainly due to the exceptionally high content of the gamma-2 (γ2) phase

in the microstructures of the modified alloy. Furthermore, the ductility of the Cu-Al-Ni

SMAs increased from 1.65 to 7.0 % when 1.14 wt. % Co was added and the alloy undergone

aging treatment where the fracture surfaces showed more ductile features and less brittle

cleavages. It was also found that Cu-Al-Ni SMAs with 1.14 wt. % Co obtained full shape

recovery after being aged at 523 K for 48 hours.

vi

ABSTRAK

Aloi ingatan bentuk (SMA) Nikel-Titanium (Ni-Ti) telah digunakan dalam banyak

aplikasi kejuruteraan dan perubatan. Walau bagaimanapun, kegunaan aloi tersebut adalah

terhad disebabkan suhu penjelmaan rendah, kesukaran dalam pemprosesan dan kos bahan

mentah yang tinggi. Sebagai bahan alternatif kepada aloi Ni-Ti, aloi berasaskan kuprum

telah berjaya digunakan. Aloi Cu-Al-Ni adalah antara SMA berasaskan kuprum digunakan

dalam pelbagai aplikasi, terutamanya jika suhu yang tinggi diperlukan. Walau bagaimanapun

Cu-Al-Ni SMA juga mempunyai kekurangan seperti kemuluran yang sangat rendah dan

terikan pemulihan yang rendah. Oleh itu, kajian ini bertujuan untuk meningkatkan

kemuluran dan kesan ingatan bentuk Cu-Ni-Al melalui tambahan unsur mengaloi dan

rawatan haba penuaan. Logam asas Cu-Al-Ni dituang tanpa dan dengan jumlah berbeza

unsur mengaloi keempat, iaitu titanium (Ti), mangan (Mn) dan cobalt (Co). Aloi diubahsuai

dan tidak diubah suai telah dihomogenkan dan dilakukan rawatan penuaan pada suhu 373 K,

423 K, dan 523 K selama 24 dan 48 jam. Penjelmaan fasa dan perubahan mikrostruktur

telah dicirikan dengan menggunakan teknik seperti kemikroskopan optik, kemikroskopan

elektron imbasan pancaran medan (FESEM), spektrometri serakan tenaga (EDS), permeteran

kalori pengimbasan kebezaan (DSC), pembelauan sinar-X (XRD) dan kemikroskopan

elektron penghantaran (TEM). Sifat tegangan dan kekerasan ditentukan masing-masing

dengan mesin Instron tegangan semesta dan mesin ujian kekerasan Vicker. Ujian ingatan

bentuk telah dilakukan dengan menggunakan mesin tegangan direka khas yang dilengkapi

dengan pita pemanasan. Keputusan kajian mendedahkan bahawa penambahan unsur

mengaloi dan rawatan penuaan didapati mengawal morfologi fasa, orientasi dan saiz bijian

bersama dengan pembentukan mendakan, oleh itu ciri ingatan bentuk, kemuluran dan

kekerasan didapati bertambah baik. Pecahan isipadu, saiz, dan taburan mendakan

terutamanya bergantung kepada jenis dan jumlah unsur mengaloi serta keadaan rawatan

penuaan. Cu-Al-Ni dengan penambahan 0.76 % berat Ti dan telah melalui rawatan penuaan

menunjukkan pemulihan lengkap selepas ujian ingatan bentuk. Ini boleh dikaitkan dengan

jumlah yang tinggi mendakan fasa-X dan penghalusan bijian yang membawa kepada mobiliti

terhad antara muka varian martensit dan kehelan. Kajian ini mendapati bahawa aloi dengan

1.14 % berat Co memberi peningkatan keseluruhan yang terbaik dari segi suhu penjelmaan,

kemuluran dan pemulihan ingatan bentuk. Peningkatan ini terutamanya disebabkan oleh

kehadiran yang sangat tinggi daripada fasa gamma-2 (γ2) dalam mikrostruktur aloi yang

diubah suai. Kemuluran Cu-Al-Ni SMA meningkat daripada 1.65% kepada 7.0 % apabila

1.14 % berat Co unsur mengaloi ditambah dan aloi menjalani rawatan penuaan di mana

permukaan patah menunjukkan lebih ciri mulur dan kurang belahan rapuh. Hasil kajian juga

menunjukkan bahawa Cu-Al-Ni SMA dengan 1.14 % berat Co mencapai pemulihan bentuk

penuh selepas melalui rawatan penuaan pada suhu 523 K selama 48 jam.

vii

TABLE OF CONTENTS

CHAPTER TITLE PAGE

DECLARATION ii

DEDICATION iii

ACKNOWLEDGEMENT iv

ABSTRACT v

ABSTRAK vi

TABLE OF CONTENTS vii

LIST OF TABLES xiii

LIST OF FIGURES xvii

LIST OF ABBREVIATIONS xxxii

LIST OF SYMBOLS xxxiii

LIST OF APPENDICES xxxv

1 INTRODUCTION 1

1.1 Background of Research 1

1.2 Problem Statement 4

1.3 Purpose of the Research 4

1.4 Objectives of the Research 5

1.5 Scopes of the Research 5

1.6 Significance of the Research 6

2 LITERATURE REVIEW 7

2.1 Introduction 7

2.2 The Development History of Shape Memory Alloys 9

viii

2.3 Martensitic Transformation in Shape Memory Alloys 10

2.4 Shape Memory Effect 19

2.5 Pseudoelasticity 20

2.6 Types of Shape Memory Alloys 21

2.6.1 Titanium-Based Shape Memory Alloys

(NiTi)

22

2.6.2 Copper-Based Shape Memory Alloys 22

2.6.3 Other Shape Memory Alloys 24

2.7 Phase Transformation and Structure of Cu-Al-Ni

Shape Memory Alloys

25

2.7.1 Phase Diagram 26

2.7.2 Martensitic Transformation 28

2.7.3 Martensitic Stabilization 29

2.8 Effects of Alloying Elements on the Cu-Al-Ni SMA 30

2.8.1 Martensitic Transformation Temperature of

Cu-Al-Ni SMA

30

2.8.2 Martensitic Structure of Cu-Al-Ni SMA 34

2.8.3 Mechanical Properties of Cu-Al-Ni SMA 39

2.9 Effects of Aging Treatment and Thermal Treatment

on the Cu-Al-Ni SMA

43

2.9.1 Martensitic Transformation Temperature of

Cu-Al-Ni SMA

43

2.9.2 Martensitic Structure of Cu-Al-Ni SMAs 47

2.9.3 Mechanical Properties of Cu-Al-Ni SMAs 52

2.9.4 Other Properties 57

2.10 Fabrication of Cu-Al-Ni Shape Memory Alloys 59

2.10.1 Melting and Casting Process 59

2.10.2 Powder Metallurgy 60

2.10.3 Melt Spinning 61

2.11 Shape Memory Alloy Applications 62

2.12 Summary

66

ix

3 RESEARCH METHODOLOGY 68

3.1 Introduction 68

3.2 Materials 70

3.3 Production of the materials by casting process 71

3.4 Homogenization Process 72

3.5 Sample Preparation for Materials Analysis and

Testing

72

3.5.1 Cutting 72

3.5.2 Grinding 73

3.5.3 Polishing 73

3.5.4 Etching 73

3.6 Materials characterization of Cu-Al-Ni SMAs 74

3.6.1 Inductively Coupled Plasma Mass

Spectrometry (ICP-MS)

74

3.6.2 X-Ray Diffractometry (XRD) 75

3.6.3 Optical and Electron Microscopy Studies 75

3.6.4 Differential Scanning Calorimetry (DSC) 76

3.7 Mechanical Test 77

3.7.1 Microhardness Test 77

3.7.2 Tensile Test 78

3.7.3 Shape Memory Effect Test (SME) 78

3.8 Aging Treatment 80

4 RESULTS AND DISCUSSION 81

4.1 Introduction 81

4.2 Evolution of the Microstructural Characteristics and

Mechanical Properties of Cu-Al-Ni SMA

82

4.2.1 Microstructural Characteristics 82

4.2.2 Transformation Temperatures 88

4.2.3 Tensile and Microhardness Tests 90

4.2.4 Shape Memory Effect Test 93

4.3 Evaluation of the Microstructural Characteristics,

Transformation Temperature, and Mechanical

x

Properties of Cu-Al-Ni-XTi SMAs 95



4.3.3 Mechanical Properties 106

4.3.3.1 Tensile and Microhardness Tests 106

4.3.3.2 Shape Memory Effect Test 109



Properties of Cu-Al-Ni-XMn SMAs

111








Properties of Cu-Al-Ni-XCo SMA

126





4.5.3.2 Shape Memory Effect of Cu-Al-

Ni-XCo SMAs

148


Mechanical Properties of aged Cu-Al-Ni SMA

143







Mechanical Properties of aged Cu-Al-Ni-XTi SMAs

156


xi






Mechanical Properties of aged Cu-Al-Ni-XMn SMAs

184







Mechanical Properties of aged Cu-Al-Ni-XCo SMAs

210






4.10 Shape memory characteristics of SMA due to the effect

of alloying and aging

238

4.10.1 Introduction 238

4.10.2 Microstructural characteristics 238

4.10.3 Transformation temperatures 239

4.10.4 Mechanical properties and Shape Memory

Behavior

240

5 CONCLUSIONS AND RECOMMENDATIONS FOR

FUTURE WORK 243

5.1 Conclusions 243

5.2 Recommendations for future work 245

xii

REFERENCES 246

Appendices A 267

Appendices B 277

xiii

LIST OF TABLES

TABLE NO TITLE PAGE

2.1 Properties of copper-based shape memory alloys 24

3.1 Chemical composition of the cast materials used in

the research

70

4.1 The transformation temperatures of Cu-Al-Ni shape

memory alloy

89

4.2 Lattice parameters of Cu-Al-Ni SMA with Ti

additions

101

4.3 Transformation temperatures of Cu-Al-Ni SMA

with Ti additions

105

4.4 Thermodynamic parameters of Cu-Al-Ni SMA

with Ti additions

106

4.5 Fracture stress-strain, microhardness and strain

recovery ratio of Cu-Al-Ni SMA with Ti additions

107

4.6 Lattice parameters of Cu-Al-Ni SMA with the Mn

additions.

116

4.7 Transformation temperatures of Cu-Al-Ni SMA

with Mn additions

120

4.8 Thermodynamic parameters of Cu-Al-Ni SMA with

Mn additions

121

4.9 The fracture stress-strain, microhardness and strain

recovery ratio of Cu-Al-Ni SMA with Mn

additions.

122

4.10 Lattice parameters and crystallite size of Cu-Al-Ni

SMA with Co additions

132

xiv

4.11 Transformation temperature of Cu-Al-Ni SMA with

Co additions

137

4.12 Thermodynamic parameters of Cu-Al-Ni SMA with

Co additions

138

4.13 Fracture stress-strain, microhardness and strain

recovery ratio of Cu-Al-Ni SMA with Co additions

139

4.14 Lattice parameters of Cu-Al-Ni SMA under

different aging conditions

148

4.15 Transformation temperature of aged Cu-Al-Ni

SMA under different aging conditions

151

4.16 Thermodynamic parameters of Cu-Al-Ni SMA

under different aging conditions

151


recovery ratio of aged Cu-Al-Ni SMA at different

conditions.

153

4.18 Lattice parameters of Cu-Al-Ni-0.37 wt. % Ti SMA

under different aging conditions

166

4.19 Lattice parameters and crystallite size of Cu-Al-Ni-

0.76 wt.% Ti SMA under different aging conditions

166

4.20 Lattice parameters and crystallite size of Cu-Al-Ni-

0.99 wt.% Ti SMA under different aging conditions

166

4.21 Transformation temperatures of aged Cu-Al-Ni-

0.37 wt. % Ti SMA under different conditions.

168



169



170

4.24 Thermodynamic parameters of Cu-Al-Ni-0.37 wt.

% Ti SMA under different aging conditions

171



171



171

xv


recovery ratio of aged Cu-Al-Ni- 0.37 wt. % Ti

SMA .

174


recovery ratio of aged Cu-Al-Ni-0.76 wt. % Ti

SMA

174


recovery ratio of aged Cu -Al -Ni-0.99 wt. % Ti

SMA

175

4.30 Lattice parameters of Cu-Al-Ni-0.39 wt. % Mn


192

4.31 Lattice parameters of Cu-Al-Ni-0.71 wt. % Mn


193

4.32 Lattice parameters of Cu-Al-Ni-0.97 wt.% Mn


193


0.39 wt. % Mn SMA under different conditions

195



196



197


% Mn SMA under different aging conditions

198



199



199


recovery ratio of aged Cu-Al-Ni-0.39 wt. % Mn

SMA at different conditions

202




203

xvi




203

4.42 Lattice parameters of Cu-Al-Ni-0.42 wt. % Co


220



220



220


0.42 wt. % Co SMA under different conditions.

223



224



225


% Co SMA under different aging conditions

225



225



226


recovery ratio of aged Cu-Al-Ni-0.42 wt. % Co

SMA at different conditions.

229




230




230

xvii

LIST OF FIGURES

FIGURE NO TITLE PAGE

2.1 Temperature-induced phase transformation of an

SMA without mechanical loading. 12

2.2 Schematic of the shape memory effect of an

SMA showing the detwinning of the material

with an applied stress. 13

2.3 Schematic of the shape memory effect of an

SMA showing the unloading and subsequent

heating to austenite under no load condition. 14

2.4 Temperature-induced phase transformation in

the presence of applied load. 15

2.5 A pseudoelastic loading path. 16

2.6 Schematic of a pseudoelastic stress-strain

diagram. 16

2.7 Schematic of a stress-temperature phase diagram

for an SMA. 17

2.8 Stress-Temperature diagram in the martensitic and

austenitic domains. 18

2.9 Schematic diagram of stress-strain-temperature

for the involved crystallographic changes during

the phenomena of SME. 19

2.10 The two loading paths discussed for

pseudoelasticity in single crystal SMA. 21

xviii

2.11 Ternary phase diagram Cu-Al-Ni, vertical cross-

section at 3 wt. % Ni. 26

2.12 Schematic phase diagram of Cu-Al-Ni alloy in

temperature-stress coordinates. 27

2.13 Evolution of (a) DSC heating-cooling curves (b)

the Ms transformation temperature and (c) the

transformation enthalpy of the as a function of

Al content. 32

2.14 Differential scanning calorimetry profiles for

Cu-Al-Ni alloys: (a) Cu-Al-Ni; (b) Cu-Al-Ni-

0.2Ti; (c) Cu-Al-Ni-0.4 Mn;(d) Cu-Al-Ni-0.2Zr. 33

2.15 Optical micrographs for alloys: (a) Cu-9.9wt. %

Al-4.43 wt. % Ni, (b) Cu- 22.11 wt. % Al- 7..4

wt. % Ni and (c) Cu- 22.41 wt. % Al- 7..4 wt. %

Ni 35

2.16 SEM micrographs of (a) Cu-13.0Al-4Ni (b) Cu-

13.5Al-4Ni, (c) Cu-13.7Al-4Ni, and (d) Cu-

14.0Al-4Ni SMAs 36

2.17 Optical micrographs of a) Cu-1 1.85wt.% Al-

3.2wt.% Ni- 3wt.% Mn, b) Cu-11.9wt.% Al-

5wt.% Ni- 2wt.% Mn-1wt.% Ti, c) Cu-

11.4wt.% Al-2.5wt.% Ni- 5wt.% Mn-0.4wt.%

Ti, and d) Cu-1 1.8wt.% Al- 5wt.% Ni-2wt.%

Mn-1%wt.% Ti 37

2.18 Optical micrographs of Cu–Al–Ni alloys: (a)

Cu–Al–Ni; (b) Cu–Al–Ni–0.2Ti; (c) Cu–Al–Ni–

0.4Mn; (d) Cu–Al–Ni–0.2Zr 38

2.19 Variation in the (a) transition stress, (b)

fracture strain, and (c) fracture stress versus

grain size 40

2.20 Tensile fracture surfaces at room temperature for

(a) Cu-13.4Al-3.8Ni SMA, (b) Cu-13.2Al-

3.04Ni-0.36Ti SMA, (c) Cu-13.0Al-2.9Ni-0.36

xix

Ti-0.22 Mn SMA and (d) Cu-13.4Al-3.05Ni-

0.24 Ti- 0.63 Zr SMA

41

2.21 Recoverable strain vs. bend-relaxing time of Cu-

Al-Ni and Cu-Al-Ni-Be 42

2.22 Stress-strain curves of SMA samples at room

temperature (25°C) 42

2.23 Transformation temperatures of the alloy wires

treated at different thermal treatment

temperatures 45

2.24 DSC thermograms of (a) Cu–14.1Al–4.0Ni wt.

% and (b) Cu–13.4Al–4.0 Ni wt. % at different

conditions 45

2.25 Changes of transformation temperatures with

various aging times in Cu-Al-Ni alloy 47

2.26 Optical micrographs of Cu–13.4Al–4.0Ni wt. %

in the: (a) as-grown and (b) aged (523 K)

conditions 49

2.27 SEM micrographs of the aged Cu–14.1Al–4.0Ni

wt. % at: (a) 473 K and (b) 573 K 49

2.28 Structures of biphasic cell germination after 10

min (a) and 20 min (b) at 400 oC 50

2.29 The schematic process of the precipitation of

biphasic cell and nanoprecipitates at 400 oC,

with zoom of α area 50

2.30 Morphologies of γ2 phase in longitudinal cross

sections of the alloy wires treated at different

heat treatment temperatures: (a) 700 oC, (b) 730

oC, (c) 750

oC, (d) 760◦ C, (e) 770

oC, and(f) 780

oC 52

2.31 Tensile stress–strain response of (a) Cu–14.1Al–

4.0Ni wt. % and (b) Cu–13.4Al–4.0Ni wt. % in

the as-quenched and aged (at 473 K for 24 h)

conditions 54

2.32 Variation of compressive transformation stresses

Cu-14.1Al-4.0Ni wt. % and Cu-13.4Al-4.0Ni wt.

xx

% with aging 54

2.33 Figure 2.33 σ-ε curves at room temperature for

(a) aged and (b) un-aged samples 55

2.34 The variation of Vickers hardness for Cu-Al-Ni

SMA with the holding time at room temperature

a) aging at room temperature after quenching b)

aging at room temperature after annealing at 330

oC for 30 mins 56

2.35 Variation of Vickers hardness with various aging

times 56

2.36 The changes in hardness (a), electrical resistivity

(b) and transformation temperatures (c) in Cu-

11.88 wt.% Al -5.06 wt.% Ni- 1.65 wt.% Mn-

0.96 wt.%Ti alloy after aging at 250°C and

300°C 58

2.37 The changes in hardness (a), electrical resistivity

(b) and transformation temperatures (c) in Cu-

11.88 wt.% Al-5.06 wt. % Ni- 1.65wt. % Mn-

0.96 wt. %Ti alloy after aging at 350°C and

400°C 59

2.38 Scheme of a powder metallurgy method. 61

2.39 The scheme of a free jet melts spinner. 62

2.40 Operating temperature range for automobiles

applications and the transformation temperatures

for selected commercially available and

developed SMAs 64

3.1 Flow chart for the research methodology 69

3.2 Production of the cast materials (a) Schematic of

the whole process, (b) Silicon carbide crucible,

(c) Cast iron mold, (d) Cast ingot 71

3.3 Schematic of Differential scanning calorimeter

curve showing critical transformation

temperatures 77

xxi

3.4 a) Instron universal tensile testing machine, b)

schematic of tensile specimen 78

3.5 Shape memory effect test; (a) Experimental; (b)

Schematic includes (1) Un-deformed sample, (2)

Deformed sample, (3) Preheating the deformed

samples above Af, (4) Sample after recovery. 79

3.6 Schematic diagram of the aging treatment 80

4.1 Microstructure of the Cu-Al-Ni SMA; a) Optical

micrograph; b) Scanning electron micrograph. 83

4.2 SEM and EDS analysis of the Cu-Al-Ni (a)

Micrograph of scanned area; (b) Spectrum 1; (c)

Spectrum 2 84

4.3 Optical micrograph of Cu-Al-Ni SMA shows γ`1

and β`1 phase 85

4.4 X-ray diffraction patterns of Cu-Al-Ni SMA 86

4.5 TEM images corresponding with selected area

diffraction patterns of Cu-Al-Ni SMA: (a) Bright

field of TEM image, (b) HRTEM image, (c)

Selected area diffraction patterns. 87

4.6 Differential Scanning Calorimetry (DSC) curves

of the Cu-Al-Ni SMA. 88

4.7 Stress-strain curves of Cu-Al-Ni SMA obtained

from the tensile test performed at room

temperature. 91

4.8 Fracture surface of the Cu-Al-Ni SMA after

tensile test (a) Low magnification, (b) High

magnification 92

4.9 Shape memory effect curve of the Cu-Al-Ni

SMA, ε_r is residual strain; ε_p is plastic strain 94

4.10 Micrographs showing the microstructures of the

Cu-Al-Ni SMA with different concentration of

Ti additions: a,d) Cu-Al-Ni-0.37 wt. % Ti SMA,

b,e) Cu-Al-Ni-0.76 wt.% Ti SMA, c,f) Cu-Al-

xxii

Ni-0.99 wt.% Ti SMA. 97

4.11 EDS analysis of the Cu-Al-Ni-0.99 wt. % Ti

SMA (a) Micrograph of scanned area; (b)

Spectrum 1; (c) Spectrum 2. 98

4.12 X-ray diffraction patterns of a) Cu-Al-Ni-0.37

wt. % Ti, b) Cu-Al-Ni-0.76 wt. % Ti, c) Cu-Al-

Ni-0.99 wt. % Ti. 99


diffraction patterns of Cu-Al-Ni-0.76 wt. % Ti

SMA: a) Bright field of TEM image, b) HRTEM

image, c) The selected area diffraction pattern. 102

4.14 An Elemental distribution map of Cu-Al-Ni-0.99

wt. % Ti SMA elemental, (a) Scanned area, (b)

Aluminum, (c) Titanium, (d) Nickel, and (e)

Copper distribution 103

4.15 Transformation temperature curves of the Cu-

Al-Ni SMA with different percentage of Ti

addition, (a) DSC curves, (b) Heating curve, and

(c) Cooling curve 104

4.16 Tensile stress-strain curves of Cu-Al-Ni SMA

with Ti addition 107

4.17 Fracture surfaces of the alloys: a) Cu-Al-Ni-0.37

wt. % Ti, b) Cu-Al-Ni-0.76 wt. % Ti, c) Cu-Al-

Ni-0.99 wt. % Ti. 108

4.18 Shape memory effect curves of Cu-Al-Ni-XTi

SM alloys 110

4.19 Micrographs showing the microstructures of the

Cu-Al-Ni SMA with different concentration of

Mn additions: a,d) Cu-Al-Ni-0.39 wt.% Mn, b,e)

Cu-Al-Ni-0.71 wt.% Mn, c,f) Cu-Al-Ni-0.97

wt.% Mn. 112

4.20 EDS analysis of the Cu-Al-Ni-0.97 wt. % Mn,

(a) Micrograph of scanned area; (b) Spectrum 1;

xxiii

(c) Spectrum 2, (d) Spectrum 3. 113


wt. % Mn, b) Cu-Al-Ni-0.71 wt. % Mn, c) Cu-

Al-Ni-0.97 wt. % Mn 114

4.22 An Elemental distribution map of Cu-Al-Ni-0.97

wt. % Mn SMA elemental, (a) Scanned area, (b)

Copper, (c) Aluminium, (d) Nickel, and (e)

Manganese distribution. 116


diffraction patterns of Cu-Al-Ni-0.71 wt.% Mn

and Cu-Al-Ni-0.97 wt. % Mn: a) Bright field of

TEM image of Cu-Al-Ni-0.71 Mn alloy, b)

HRTEM image of the Cu-Al-Ni-0.71 wt. %Mn

alloy, c) SADP of the Cu-Al-Ni-0.71 wt. %Mn

alloy, d) Bright field of TEM image of Cu-Al-

Ni-0.97 Mn alloy, e) HRTEM image of the Cu-

Al-Ni-0.97 wt. %Mn alloy, f) SADP of the Cu-

Al-Ni-0.97 wt. %Mn alloy. 117


Al-Ni SMA with different percentage of Mn

addition

120


with Mn addition 122

4.26 Fracture surfaces of the alloys: a) Cu-Al-Ni-0.39

wt. % Mn, b) Cu-Al-Ni-0.71 wt. % Mn, c) Cu-

Al-Ni-0.97 wt. % Mn. 123

4.27 Shape memory effect curves of the alloys at 373

K, then preheated to 676 K.. 125

4.28 Micrographs showing the microstructure of Cu-

Al-Ni SMA with different concentration of Co

additions: a,d) Cu-Al-Ni-0.42 wt. % Co, b,e) Cu-

Al-Ni-0.7 wt. % Co, c,f) Cu-Al-Ni-1.14 wt. %

Co. 128

xxiv

4.29 EDS analysis of Cu-Al-Ni-1.14 wt. % Co (a)

Micrograph of scanned area; (b) Spectrum 1; (c)

Spectrum 2. 129

4.30 Volume fraction and size of γ2 precipitates of Cu-

Al-Ni-XCo (0.42, 0.72, and 1.14 wt. %). 129


wt. % Co, b) Cu-Al-Ni-0.72 wt. % Co, c) Cu-Al-

Ni-1.14 wt.% Co. 130

4.32 TEM images the corresponding with selected

area diffraction patterns of Cu-Al-Ni-0.72 wt. %

Co and Cu-Al-Ni-1.14 wt. % Co: a) Bright field

of TEM image of Cu-Al-Ni-0.72 wt. % Co alloy,

b) HRTEM image of the Cu-Al-Ni-0.72 wt. %

Co alloy, c) SADP of the Cu-Al-Ni-0.72 wt. %

Co alloy, d) Bright field of TEM image of Cu-

Al-Ni-1.14 wt.%. % Co alloy, e) HRTEM image

of the Cu-Al-Ni-1.14 wt. % Co alloy, f) SADP

of the Cu-Al-Ni-1.14 wt. % Co alloy. 133

4.33 An Elemental distribution map of Cu-Al-Ni-

1.14 wt.% Co SMA elemental, (a) Scanned area,

(b) Aluminium, (c) Cobalt, (d) Nickel, and (e)

Copper distribution. 135


Al-Ni SMA with different percentage of Co

addition

136

4.35 Evaluation of the martensite-austenite

transformation temperatures as a function of Co

additions 137


with Co addition 139

4.37 Fracture surface: a) Cu-Al-Ni SMA, b) Cu-Al-

Ni-0.42 wt. % Co SMA, b) Cu-Al-Ni-0.72 wt. %

Co SMA, c) Cu-Al-Ni-1.14 wt. % Co SMA 140

xxv

4.38 Shape memory effect curves of the Cu-Al-Ni-

XCo alloys 142

4.39 FESEM micrographs shows the microstructures

of the Cu-Al-Ni SMA under different aging

conditions: a) 373 K for 24hr, b) 373 K for 48hr,

a) 423 K for 24hr, b) 423 K for 48hr, a) 250 °C

for 24hr, b) 250 °C for 48hr. 144

4.40 EDS analysis of the Cu-Al-Ni (a) Micrograph of

scanned area; (b) Spectrum 1; (c) Spectrum 2; d)

Spectrum 3. 146

4.41 X-ray diffraction patterns of Cu-Al-Ni SMA, a)

373 K for 24hr, b) 373 K for 48hr, c) 423 K for

24hr, d) 423 K for 48hr, e) 523 K for 24hr, f)

523 K for 48hr. 147

4.42 Transformation temperature curves on the

heating and cooling cycle of the Cu-Al-Ni SMA

aged at 423 K for 24 hr. 150

4.43 Tensile stress-strain curves for the aged Cu-Al-

Ni SMA. 152

4.44 Fracture surface of Cu-Al-Ni SMA at different

aging conditions: a) 373 K for 24hr, b) 373 K for

48hr, c) 423 K for 24hr, d) 423 K for 48hr, e)

523 K for 24hr, f) 523 K for 48hr. 154

4.45 Shape memory effect curves of the aged Cu-Al-

Ni SMA 156

4.46 FESEM micrographs show the microstructures

of the Cu-Al-Ni-0.37 wt. % Ti SMA under

different aging conditions: a) 373 K for 24hr,

b)373 K for 48hr, c) 423 K for 24hr, d) 423 K

for 48hr, e) 523 K for 24hr, f)523 K for 48hr. 159


of the Cu-Al-Ni-0.76 wt.% Ti SMA under

different aging conditions: a) 373 K for 24hr,

xxvi

b)373 K for 48hr, c) 423 K for 24hr, d)423 K for

48hr, e) 523 K for 24hr, f)523 K for 48hr.

160


of the Cu-Al-Ni-0.99 wt.% Ti SMA under

different aging conditions: a) 373 K for 24hr, b)

373 K for 48hr, c) 423 K for 24hr, d) 423 K for

48hr, e) 523 K for 24hr, f) 523 K for 48hr. 161

4.49 X-ray diffraction patterns of Cu-Al-Ni-0.37 wt.

% Ti SMA, a) 373 K for 24hr, b)373 K for 48hr,

c) 423 K for 24hr, d)423 K for 48hr, e) 523 K for

24hr, f)523 K for 48hr. 163

4.50 X-ray diffraction patterns of Cu-Al-Ni-0.76

wt.% Ti SMA, a) 373 K for 24hr, b)373 K for

48hr, c) 423 K for 24hr, d)423 K for 48hr, e) 523

K for 24hr, f)523 K for 48hr. 164


wt.% Ti SMA, a) 373 K for 24hr, b)373 K for


K for 24hr, f)523 K for 48hr. 165


Al-Ni-0.37 wt. % Ti SMA aged at 523 K for 24

hr. 168

4.53 DSC diagrams of the heating and cooling cycle

of the Cu-Al-Ni-0.76 wt.% Ti SMA aged at 523

K for 24 hr. 169

4.54 DSC diagrams of the heating and cooling cycle

of the Cu- Al- Ni- 0.99 wt.% Ti SMA aged at

523 K for 24 hr. 170

4.55 Tensile stress-strain curves for SMA: a) Cu - Al-

Ni -0.37 wt. % Ti; b) Cu -Al- Ni -0.76 wt. % Ti;

c) Cu- Al -Ni -0.99 wt. % Ti. 173

4.56 Fracture surface of Cu-Al-Ni- 0.37 wt. % Ti

SMA at different aging conditions: a) 373 K for

xxvii

24hr, b)373 K for 48hr, c) 423 K for 24hr, d)423

K for 48hr, e) 523 K for 24hr, f)523 K for 48hr.

177

4.57 Fracture surface of Cu-Al-Ni- 0.76 wt.% Ti



K for 48hr, e) 523 K for 24hr, f)523 K for 48hr. 178

4.58 Fracture surface of Cu-Al-Ni- 0.99 wt.% Ti




4.59 SME curves of the aged Cu-Al-Ni-0.37 wt. % Ti

SMA 182

4.60 SME curves of the aged Cu-Al-Ni-0.76 wt. % Ti

SMA. 183

4.61 Shape memory effect curves of the aged Cu-Al-

Ni-0.99 wt. % Ti SMA 183

4.62 FESEM micrographs showing the

microstructures of the Cu-Al-Ni- 0.39wt. % Mn

SMA under different aging conditions: a) 373 K

for 24hr, b) 373 K for 48hr, c) 423 K for 24hr, d)

423 K for 48hr, e) 523 K for 24hr, f) 523 K for

48hr. 186


microstructures of the Cu-Al-Ni- 0.71 wt.% Mn




48hr.

187


microstructures of the Cu-Al-Ni- 0.97 wt.% Mn



xxviii


48hr.

188

4.65 X-ray diffraction patterns of aged Cu-Al-Ni-

0.39wt. % Mn SMA, a) 373 K for 24hr, b)373 K

for 48hr, c) 423 K for 24hr, d) 423 K for 48hr, e)

523 K for 24hr, f)523 K for 48hr. 189

4.66 X-ray diffraction patterns of aged Cu-Al-Ni-0.71

wt.% Mn SMA, a) 373 K for 24hr, b)373 K for


K for 24hr, f)523 K for 48hr.

190

4.67 X-ray diffraction patterns of aged Cu-Al-Ni-0.97

wt.% Mn SMA, a) 373 K for 24hr, b) 373 K for

48hr, c) 423 K for 24hr, d) 423 K for 48hr, e)

523 K for 24hr, f) 523 K for 48hr. 191

4.68 DSC diagrams on the heating and cooling cycle

of the Cu-Al-Ni-0.39 wt. % Mn SMA aged at

523 K for 24hr. 195



523 K for 24hr. 196



523 K for 24hr. 197


Ni-0.39 wt. % Mn; b) Cu-Al-Ni-0.71 wt.% Mn;

c) Cu- Al -Ni -0.97 wt. % Mn. 202

4.72 Fracture surface of the aged Cu-Al-Ni-0.39wt. %

Mn SMA at different aging conditions: a) 373 K



48hr.

205

4.73 Fracture surface of the aged Cu-Al-Ni-0.71 wt.%


xxix



48hr.

206

4.74 Fracture surface of the aged Cu-Al-Ni-0.97 wt.%


for 24hr, b)373 K for 48hr, c) 423 K for 24hr,

d)423 K for 48hr, e) 523 K for 24hr, f)523 K for

48hr. 207

4.75 SME curves of the aged Cu-Al-Ni-0.39wt. %

Mn SMA

208

4.76 SME curves of the aged Cu-Al-Ni-0.71 wt. %

Mn SMA 208


Mn SMA 209


microstructures of the Cu-Al-Ni-0.42 wt. % Co




48 hr. 213






48 hr. 214






48 hr.

215

4.81 X-ray diffraction patterns of Cu-Al-Ni-0.42 wt.

xxx

% Co SMA, a) 373 K for 24hr, b) 373 K for


K for 24hr, f) 523 K for 48hr.

217


wt.% Co SMA, a) 373 K for 24hr, b) 373 K for


K for 24hr, f)523 K for 48hr. 218


wt.% Co SMA, a) 373 K for 24hr, b) 373 K for


K for 24hr, f)523 K for 48hr. 219


of the Cu-Al-Ni-0.42 wt. % Co SMA aged at

523 K for 24 hr. 222


of the Cu-Al-Ni-0.72 wt.% Co SMA aged at 523

K for 24 hr. 223


of the Cu-Al-Ni-1.14 wt.% Co SMA aged at 523

K for 24 hr. 224


Ni -0.42 wt. % Co; b) Cu -Al- Ni -0.72 wt. %

Co; c) Cu- Al -Ni -1.14 wt. % Co. 228

4.88 Fracture surface of Cu-Al-Ni-0.42 wt. % Co




4.89 Fracture surface of Cu-Al-Ni-0.72 wt.% Co




233

4.90 Fracture surface of Cu-Al-Ni-1.14 wt.% Co


xxxi



234


Co SMA. 236


Co SMA. 237


Co SMA. 237

4.94 DSC curves of the Cu-Al-Ni SMA with and

without addition of alloying elements (a) heating

and (b) cooling 240

4.95 Shape memory effect curves of the modified and

unmodified alloys before aging treatment 242

4.96 Shape memory effect curves of the modified and

unmodified alloys after aging treatment 242

xxxii

LIST OF ABBREVIATIONS

Cu-Al-Ni - Copper Aluminum Nickel

DSC - Differential scanning calorimetry

EDS - Energy dispersive spectroscopy

FE-SEM - Field emission scanning electron microscopy

HRTEM - High resolution transmission electron microscopy

ICP-MS - Inductive couple plasma- mass spectroscopy

OM - Optical microscope

SADP - Selected area diffraction pattern

SEM - Scanning electron microscopy

SMAs - Shape memory alloys

SME - Shape memory effect

TEM - Transmission electron microscopy

XRD - X-ray diffraction

xxxiii

LIST OF SYMBOLS

(hkl) - Miller indices

- Enthalpy of Martensite → Austenite

- Enthalpy of Austenite → Martensite

- Entropy of Martensite → Austenite

- Entropy of Austenite → Martensite

- Fracture strain

- Strain after heating above Af

- Residual strain

- Strain recovery ratio by shape memory effect

- Fracture stress

a, b, and c - Lattice parameters

a.u - arbitrary unit

Af - Austenite finish temperature

As - Austenite start temperature

B - Full width at half maximum

d - Spacing distance

G - Gibbs free energy

Hv - Vicker‟s hardness

K/min - Kelvin per minute

Mf - Martensite finish temperature

Ms - Martensite start temperature

oC - Centigrade degree

T - Temperature

To - Equilibrium temperature

xxxiv

Wt.% - Weight percentage

α, β - Lattice angles

θ - Bragg‟s angle

λ - Wavelength

G.B - Grain boundary

xxxv

LIST OF APPENDICES

APPENDIX TITLE PAGE

A DSC curves of the aged Cu-Al-Ni-Xy (X is Ti,

Mn, and Co; y is weight percentage)

267

B Publications 277

1

CHAPTER 1

INTRODUCTION

1.1 Background of Research

Shape memory alloys (SMAs) and their associated thermoelastic martensitic

transformation have been the subject of extensive studies for many years, since they

have many technological applications utilizing the shape memory effect [1, 2].

Typical for shape memory material is a unique, unconventional correlation of

temperature, stress and strain that crystallographic reversible thermo-elastic

martensitic transformation forms its basis. Since technological applications impose

reliability requirements on commercial SMAs, the MT (martensitic transformation)

in particular need to be highly reproducible [3]. As a result, controlling the

martensite type and the MT temperatures becomes a basic point for determining the

SMA‟s thermo-mechanical and hysteresis properties. Since extreme sensitivity is

shown towards concentration changes by MT temperatures, controlling quaternary or

ternary alloys‟ concentration with a lot of precision is difficult as the composition of

the alloy is very vital in the determination of the MT temperatures. Parameters such

as structure ordering and grain size are depended upon by phase transformation

temperatures but their importance can not be compared to that of the alloy

composition. It is also worthy to note that the martensite type which is obtained is

dependent of the intermetallic alloy‟s degree of order [4] that also is independent of

2

the concentration of the alloy [5].

When compared to the many SMAs which are available, the most

commercially attractive alloys which can be employed in applications which are

practical are the Cu-based SMAs. That is because they exhibit reasonable shape

memory effect, offer the possibility of being used at high temperatures, have better

thermal stability and are not expensive. It should also be noted that the Cu-Al-Ni

alloys‟ applications have restrictions since they are associated with brittle inter-

granular cracking and poor workability and thus used where very small shape

changes are required [6]. Their grain size which is large (1-3 mm), high elastic

anisotropy ratio (~14) and the high degree of order which they are associated with is

responsible for the material failure through inter-granular fracture which they exhibit

[7-9]. The difficulty of stress concentration is enhanced by these factors at the grain

boundaries and as a result promoting fracture. Hence, poor mechanical properties are

exhibited by these alloys (fracture strain 0.5% and fracture stress 150 MPa). It has

been established by Husain [10] and Sugimoto et al [11] that within Cu-Al-Ni shape

memory alloys with a basis on β when subjected to stress, the existent elastic

anisotropy within the allows is responsible the polycrystalline samples‟ stress

concentration at the grain boundaries. High stress concentration can result due to the

large grain size. The martensitic strain‟s orientation dependence also determines the

elastic anisotropy. The alloys‟ stress relaxation properties can also be reduced by the

spinodal transformation and the existent ordered phases [12, 13].

Research work pertaining to Cu-Al-Ni SMAs is of considerable significance

since these alloys possess higher transformation temperatures [14] and higher

damping capacity [15, 16], especially at high temperatures, compared with even

Nitinol. That makes them to be well suited when being employed in engineering

applications like actuators. They fit well in actuators that operate within high

temperatures, bridges‟ damping elements, buildings, oil well applications and other

structures. It should be remembered that when Cu-Al-Ni alloys are subjected to very

high temperature service conditions, they show some susceptibility to post-quench

aging and as a result lead to a change in their mechanical properties, martensitic

phases and transformation temperatures with the time of operation [17, 18].

3

The material‟s deformation within the martensitic state (below Mf) is

influenced by the shape memory effect. A number of effects can take place over the

deformation which may lead the macroscopic shape change within Cu-Al-Ni SMAs.

Usually, self-accommodating plate variants are contained within the thermoelastic

martensitic structure. The variants rearrange and coalesce through the intervenient

boundaries‟ movement when the deformation takes place. Development of

mechanical twins may take place during this process. As a result, in response to the

stress which is applied, formation of the most favorably oriented martensite variants

occur. Additionally, when responding to the deformation, martensite → martensite

transformations which involve changes in the stacking sequence form: taking place

of austenite → martensite transformations occurs[19, 20]. There have been wide

studies regarding ro the Cu-Al-Ni SMAs‟ shape memory effect within the bending

test [20-22] though not much has been done when studies these properties under the

tensile test [23, 24].

A number of attempts have been made in improving mechanical properties.

Ductility is the property within Cu–Al–Ni SMAs that has been put into consideration

by using different techniques to do grain refining such as adding small amounts of

quaternary elements, such as Zr, V and Ti and including aging treatment [22, 25-28].

Though properties like ductility and strength were improved after that, some

mechanical properties still remained unsatisfactory to be used for some targeted

commercial applications more so when a full shape recovery was necessary. A

number of studies have been done on different aging aspects of the alloys and the

influence they have on their shape memory properties [17]. The martensite

stabilization phenomenon was given special attention since it is normally associated

the reverse transformation temperatures (As and Af)‟s increase once deformation has

taken place. Though, not many studies were done on the aged alloys‟ thermo-

mechanical response [23, 29, 30]. Thus, this research aims to study the effect of

alloying elements and aging treatments on the phase transformation behavior and

properties of Cu-Al-Ni SMAs.

4

1.2 Problem Statement

Since Cu-Al-Ni shape memory alloy has many advantages, which has attracted

more attention from the scientists and researchers, their applications are limited due

to the low recovery strain and high brittleness. Their damaging properties may be

improved by adding specific alloying elements followed by aging treatments. An

investigation into the structure and property relationship is necessary to ensure the

correct compositions of Cu-Al-Ni SMAs, which gives the optimum performance that

can achieve 100 % of the shape recovery.

1.3 Purpose of the Research

The purpose of this research is to find ways to improve the poor properties of

Cu-Al-Ni SMA in terms of its low recovery strain (40-50 %) and high brittleness (1-

1.2% fracture strain). The research induces understanding the mechanisms and

transformation behavior of the Cu-Al-Ni SMAs and identifies the influence of

alloying elements on the structure and properties of the alloys. The output of this

research is expected to improve the mechanical properties and reduce the limitation

usage for many industrial applications, e.g., actuators and sensors that will be helpful

to prevent the destruction of such structures as buildings and bridges. The effect of

various alloying materials such as Mn, Co, and Ti with different additions amounts

along with applying different aging conditions of 373 K, 423 K, and 523 K for 24

and 48 hr on the phase transformation behavior of Cu-Al-Ni SMAs are investigated

using various material characterization techniques. This study is expected to provide

the phase transformation characteristics of each alloy in accordance with their

microstructural observations, transformation temperatures and mechanical properties

such as tensile, shape memory effect, and hardness.

5

1.4 Objectives of the Research

The objectives of the research are as follows:

1. To determine the effect of different amounts of alloying elements (Ti,

Mn, and Co) on the structure and properties of the Cu-Al-Ni shape

memory alloys.

2. To investigate the effects of aging temperature and aging time on the

structure and properties of Cu-Al-Ni shape memory alloys.

3. To establish the correlation between the phase transformation

characteristics of Cu-Al-Ni SMA, with respect to the concentration of

alloying elements and aging treatment.

1.5 Scopes of the Research

The scope of the research is as follows:

1. Preparation of the samples by casting commercially pure raw metals (Cu

99.999 %, Al 99.999, and Ni 99.995 %) with and without alloying

elements e.g., Ti 99.99 %, Mn 99.99%, and Co 99.95% by using an

induction furnace.

2. Analysis of the as-cast samples by using inductively coupled plasma mass

spectrometry (ICP-MS) for composition analysis, differential scanning

calorimetry (DSC) for phase transformation temperature, and Vicker‟s

test for hardness measurement.

3. Aging treatment of the as-cast samples under different condition of

temperature and time.

4. Microstructural and phase analysis of the as-cast and aged samples using

field emission scanning electron microscopy (FESEM), X-ray diffraction

6

(XRD), and energy dispersive spectroscopy (EDS).

5. Perform the tensile test on the as-cast and aged samples in order to

determine the fracture stress and strain by using an Instron 5982-type

universal testing machine.

6. Perform shape memory test on the as-cast and aged samples using

specially designed tensile test machine.

7. Detailed analysis of selected samples after shape memory test by using

transmission electron microscope (TEM).

1.6 Significance of the Research

The basic aim of this research is to provide significant information on the

behavior of the Cu-Al-Ni SMAs with and without alloying addition and aging

treatments. Thus, the results of this research will benefit the automotive, civil and

aerospace industries using the shape memory alloys in terms of improved properties

such as ductility and reduction in brittleness. However, it gives the allowance for

these materials to be used for higher temperatures without losing its shape memory

effect. In addition, the outcomes of this research will contribute to providing a

sustainable material with better properties and extensive earthquake applications.

246

REFERENCES

1. Sarı, U. and Kırındı, T. Effects of deformation on microstructure and

mechanical properties of a Cu–Al–Ni shape memory alloy. Materials

Characterization. 2008. 59(7): 920-929.

2. Saburi, T. and Wayman, C. M. Crystallographic similarities in shape memory

martensites. Acta Metallurgica. 1979. 27(6): 979-995.

3. Recarte, V., Pérez-Sáez, R. B., San Juan, J., Bocanegra, E. H. and Nó, M. L.

Influence of Al and Ni concentration on the Martensitic transformation in Cu-

Al-Ni shape-memory alloys. Metallurgical and Materials Transactions A.

2002. 33(8): 2581-2591.

4. V Recartea, b, R.B Pérez-Sáeza, E.H Bocanegrac, M.L Nóc, J San Juan.

Dependence of the martensitic transformation characteristics on

concentration in Cu–Al–Ni shape memory alloys. Materials Science and

Engineering A. 1999. 273–275: 380-384.

5. Recarte, V., Lambri, O., Pérez-Sáez, R., Nó, M. and San Juan, J. Ordering

temperatures in Cu–Al–Ni shape memory alloys. Applied physics letters.

1997. 70(26): 3513-3515.

6. Wei, Z., Peng, H., Yang, D., Chung, C. and Lai, J. Reverse transformations in

CuAlNiMnTi alloy at elevated temperatures. Acta materialia. 1996. 44(3):

1189-1199.

7. Ma, J., Karaman, I. and Noebe, R. D. High temperature shape memory alloys.

International Materials Reviews. 2010. 55(5): 257-315.

8. Vajpai, S., Dube, R. and Sangal, S. Application of rapid solidification powder

metallurgy processing to prepare Cu–Al–Ni high temperature shape memory

alloy strips with high strength and high ductility. Materials Science and

Engineering: A. 2013. 570: 32-42.

9. Otsuka, K. and Wayman, C. M. Shape memory materials: Cambridge

university press. 1999.

247

10. Husain, S. and Clapp, P. The intergranular embrittlement of Cu-AI-Ni β-

phase alloys. Journal of materials science. 1987. 22(7): 2351-2356.

11. Sugimoto, K., Kamei, K., Matsumoto, H., Komatsu, S., Akamatsu, K. and

Sugimoto, T. Grain-refinement and the related phenomena in quaternary Cu-

Al-Ni-Ti shape memory alloys. Le Journal de Physique Colloques. 1982.

43(C4): C4-761-C764-766.

12. Zhao, J.-C. and Notis, M. Spinodal decomposition, ordering transformation,

and discontinuous precipitation in a Cu–15Ni–8Sn alloy. Acta materialia.

1998. 46(12): 4203-4218.

13. Sampath, V. Studies on the effect of grain refinement and thermal processing

on shape memory characteristics of Cu–Al–Ni alloys. Smart Materials and

Structures. 2005. 14(5): S253-S260.

14. T.W.Duerig, K. N. M., D. Stoeckel and C.M. Wayman Engineering aspects

of shape memory alloys. Materials & Design. 1990. 11(6): 301.

15. Van Humbeeck, J. and Stalmans, R. Shape Memory Alloys, Types and

Functionalities. Encyclopedia of Smart Materials: John Wiley & Sons, Inc.

2002.

16. Van Humbeeck, J. Damping capacity of thermoelastic martensite in shape

memory alloys. Journal of Alloys and Compounds. 2003. 355(1): 58-64.

17. Suresh, N. and Ramamurty, U. Aging response and its effect on the

functional properties of Cu–Al–Ni shape memory alloys. Journal of Alloys

and Compounds. 2008. 449(1-2): 113-118.

18. Suresh, N. and Ramamurty, U. Effect of aging on mechanical behavior of

single crystal Cu–Al–Ni shape memory alloys. Materials Science and

Engineering: A. 2007. 454-455: 492-499.

19. Saburi, T., Wayman, C., Takata, K. and Nenno, S. The shape memory

mechanism in 18R martensitic alloys. Acta Metallurgica. 1980. 28(1): 15-32.

20. Otsuka, K., Sakamoto, H. and Shimizu, K. Successive stress-induced

martensitic transformations and associated transformation pseudoelasticity in

Cu-Al-Ni alloys. Acta Metallurgica. 1979. 27(4): 585-601.

21. Morris, M. High temperature properties of ductile Cu-Al-Ni shape memory

alloys with boron additions. Acta metallurgica et materialia. 1992. 40(7):

1573-1586.

22. Morris, M. A. and Lipe, T. Microstructural influence of Mn additions on

248

thermoelastic and pseudoelastic properties of Cu-Al-Ni alloys. Acta

Metallurgica et Materialia. 1994. 42(5): 1583-1594.

23. Picornell, C., Pons, J. and Cesari, E. Stabilisation of martensite by applying

compressive stress in Cu-Al-Ni single crystals. Acta Materialia. 2001. 49(20):

4221-4230.

24. Sittner, P., Novak, V. and Zárubová, N. Martensitic transformations in [001]

CuAlZnMn single crystals. Acta materialia. 1998. 46(4): 1265-1281.

25. J. S. Lee; C. M. Wayman. Grain refinement of a Cu-Al-Ni shape memory

alloys by Ti and Zr additions. transactions of Japan institute of metals. 1986.

27(8): 584 -591.

26. Gao, Y., M. Zhu, J. K. L. Lai Microstructure characterization and effect of

thermal cycling and ageing on vanadium-doped Cu-Al-Ni-Mn high-

temperature shape memory alloy Journal of Materials Science. 1998. 33:

3579-3584.

27. Bhattacharya B, Bhuniya A and Banerjee M K. Influence of minor additions

on characteristics of Cu–Al–Ni alloy”, Mater. Sci. Technol. 1993. 9: 654–

658.

28. Roh, D. W., Lee, E. S. and Kim, Y. G. Effects of ordering type and degree on

monoclinic distortion of 18R-type martensite in Cu-Zn-Al alloys.

Metallurgical Transactions A. 1992. 23(10): 2753-2760.

29. S. Sugimoto, H. S., T. Hara and H. Tsuchiya The effect of grain constraint,

heat treatment and compositional change on the behavior of martensitic

transformations in alloys with the composition near Cu-13Al-4Ni-1Zn

(mass%). J. Phys. IV 1995. 5: 925.

30. Sakamoto, H. and Shimizu, K. i. Effect of Heat Treatments on Thermally

Formed Martensite Phases in Monocrystalline Cu–Al–Ni

Shape Memory Alloy. ISIJ International. 1989. 29(5): 395-404.

31. Gandhi, V. and Thompson, B. D. Smart Materials and Structures: Springer.

1992.

32. K. Otsuka, C. M. Wayman. Shape Memory Materials, reprint, illustrated ed.:

Cambridge University Press. 1999.

33. Olson, G. and Cohen, M. Stress-assisted isothermal martensitic

transformation: application to TRIP steels. Metallurgical Transactions A.

1982. 13(11): 1907-1914.

249

34. Vokoun, D. and Kafka, V. Mesomechanical modeling of shape memory

effect. Proceedings of the 1999 Symposium on Smart Structures and

Materials: International Society for Optics and Photonics. 596-601.

35. Kumar, P. and Lagoudas, D. Introduction to shape memory alloys: Springer.

2008.

36. Wayman, C. and Bhadeshia, H. Phase transformations, nondiffusive. Physical

Metallurgy. 1983. 2: 1507-1554.

37. Nishiyama, Z., Fine, M. E. and Wayman, C. M. Martensitic transformation:

Academic Press. 1978.

38. Popov, P. A. Constitutive modelling of shape memory alloys and upscaling of

deformable porous media. Texas A&M University; 2005.

39. Patoor, E., Lagoudas, D. C., Entchev, P. B., Brinson, L. C. and Gao, X. Shape

memory alloys, Part I: General properties and modeling of single crystals.

Mechanics of Materials. 2006. 38(5): 391-429.

40. Ölander, A. An electrochemical investigation of solid cadmium-gold alloys.

Journal of the American Chemical Society. 1932. 54(10): 3819-3833.

41. Greninger AB, M. V. Strain Transformation in Metastable Beta Copper-Zinc

and Beta Copper-Ti Alloys. Transactions of the Metallurgical Society of

AIME. 1938. 128: 337–368.

42. Kurdjumov GV, K. L. First reports of the thermoelastic behaviour of the

martensitic phase of Au-Cd alloys. Doklady Akademii Nauk. 1949. 66: 211-

213

43. Chang LC, Read TA.. Behavior of the elastic properties of AuCd. .

Trans Met Soc AIME. . 1951. 191(1): 47-52.

44. Kauffman, G. and Mayo, I. The Story of Nitinol: The Serendipitous

Discovery of the Memory Metal and Its Applications. The Chemical

Educator. 1997. 2(2): 1-21.

45. Buehler, W. J., Gilfrich, J. and Wiley, R. Effect of Low‐Temperature Phase

Changes on the Mechanical Properties of Alloys near Composition TiNi.

Journal of Applied Physics. 2004. 34(5): 1475-1477.

46. Van Humbeeck, J. Non-medical applications of shape memory alloys.

Materials Science and Engineering: A. 1999. 273–275(0): 134-148.

47. Sun, L., Huang, W., Ding, Z., Zhao, Y., Wang, C., Purnawali, H. and Tang,

C. Stimulus-responsive shape memory materials: a review. Materials &

250

Design. 2012. 33: 577-640.

48. Sreekumar, M., Nagarajan, T., Singaperumal, M., Zoppi, M. and Molfino, R.

Critical review of current trends in shape memory alloy actuators for

intelligent robots. Industrial Robot: An International Journal. 2007. 34(4):

285-294.

49. Baz, A., Imam, K. and McCoy, J. Active vibration control of flexible beams

using shape memory actuators. Journal of Sound and Vibration. 1990. 140(3):

437-456.

50. Duerig, T. W., Melton, K. N., Stockel, D. and Wayman, C. M. Engineering

Aspects of Shape Memory Alloys: Books on Demand. 1990.

51. Hirose, S., Ikuta, K. and Umetani, Y. Development of shape-memory alloy

actuators. Performance assessment and introduction of a new composing

approach. Advanced Robotics. 1988. 3(1): 3-16.

52. Karhu, M. and Lindroos, T. Long-term behaviour of binary Ti–49.7 Ni (at.%)

SMA actuators-the fatigue lives and evolution of strains on thermal cycling.

Smart Materials and Structures. 2010. 19(11): 115019.

53. Choon, T. W., Salleh, A. S., Jamian, S. and Ghazali, M. Phase

Transformation Temperatures for Shape Memory Alloy Wire. Enformatika.

2007. 19.

54. Ren, J. and Liew, K. Meshfree modelling and characterisation of

thermomechanical behaviour of NiTi alloys. Engineering analysis with

boundary elements. 2005. 29(1): 29-40.

55. Wada, K. and Liu, Y. Shape recovery of NiTi shape memory alloy under

various pre-strain and constraint conditions. Smart materials and structures.

2005. 14(5): S273.

56. Otsuka, K., A. Saxena, J. Deng and Xiaobing Ren Mechanism of the shape

memory effect in martensitic alloys: an assessment. Philosophical Magazine.

2011. 91(36): 4514-4535.

57. Otsuka, K. and Shimizu, K. Pseudoelasticity and shape memory effects in

alloys. International Metals Reviews. 1986. 31(1): 93-114.

58. Otsuka, K. a. X. R. Martensitic transformations in nonferrous shape memory

alloys. Materials Science and Engineering: A. 1999. 273–275(0): 89-105.

59. Macqueron, J., Morin, M., Guénin, G., Planes, A., Elgueta, J. and Castan, T.

Atomic Ordering and Martensitic Transition in a Cu-Zn-Al Shape Memory

251

Alloy. Le Journal de Physique IV. 1991. 1(C4): C4-259-C254-263.

60. Delaey, L. Diffusionless transformations. . In: Cahn, R. W., Haasen, P.,

Kramen, E.J. (Eds.), . ed. Phase Transformations in Materials, Material

Science and Technologies,. New York: VCH Publishers. 339–404; 1990.

61. Tong, H. and Wayman, C. Characteristic temperatures and other properties of

thermoelastic martensites. Acta Metallurgica. 1974. 22(7): 887-896.

62. Lagoudas, D.C. Shape Memory Alloys: Modeling and Engineering

Applications: Springer. 2008.

63. D.C.Lagoudas Shape Memory Alloys and Engineering Applications:

Springer, New York. 2008.

64. Buehler, W. J., Gilfrich, J.V., Wiley, R.C. Effects of low temperature phase

changes on the mechanical properties of alloys near composition TiNi.

Journal of Applied Physics. 1963. 34: 1475.

65. Buehler, W. J., Wiley, R.C., and 3, 851. Nickel-base alloys. 1965.

66. Jackson, C., Wagner, H. and Wasilewski, R. 55-nitinol-the alloy with a

memory: it's physical metallurgy, properties, and application. NASA Report

SP5110. 1972.

67. Melton, K. Ni-Ti Based Shape Memory Alloys. Butterworth-Heinemann,

Engineering Aspects of Shape Memory Alloys(UK), 1990. 1990: 21-35.

68. Lindquist, P. and Wayman, C. Shape Memory and Transformation Behavior

of Martensitic Ti-Pd--Ni and Ti-Pt-Ni Alloys. Butterworth-Heinemann,

Engineering Aspects of Shape Memory Alloys(UK), 1990. 1990: 58-68.

69. Strnadel, B., Ohashi, S., Ohtsuka, H., Miyazaki, S. and Ishihara, T. Effect of

mechanical cycling on the pseudoelasticity characteristics of Ti-Ni and Ti-Ni-

Cu alloys. Materials Science and Engineering: A. 1995. 203(1): 187-196.

70. Xu, Y., Shimizu, S., Suzuki, Y., Otsuka, K., Ueki, T. and Mitose, K.

Recovery and recrystallization processes in Ti-Pd-Ni high-temperature shape

memory alloys. Acta materialia. 1997. 45(4): 1503-1511.

71. Miyazaki, S. Medical and dental applications of shape memory alloys:

Cambridge: Cambridge University Press. 1999.

72. Tsunehiko Todoroki and Hirokazu Tamura. The Stress-induced

Transformation of a Ti-Ni Alloy by the Pre-load Test Method. J. Japan Inst.

Metals. 1986. 50(6): 546-554.

73. Saburi, T., Nenno, S., Nishimoto, Y. and Zeniya, M. Effects of Thermo-

252

Mechanical Treatment on the Shape Memory Effect and the Pseudoelasticity

of Ti--50. 2 Ni and Ti-47. 5 Ni--2. 5 Fe Alloys. Tetsu-to-Hagane(J. Iron Steel

Inst. Jpn.). 1986. 72(6): 571-578.

74. Saburi, T. Ti-Ni shape memory alloys. Shape memory materials. 1999: 49-

96.

75. Tadaki, T. Cu-based shape memory alloys. Shape memory materials. 1998:

97-116.

76. Miyazaki, S., Kawai, T. and Otsuka, K. Study of fracture in Cu-Al-Ni shape

memory bicrystals. Le Journal de Physique Colloques. 1982. 43(C4): C4-

813-C814-818.

77. Horikawa, H., Ichinose, S., Morii, K., Miyazaki, S. and Otsuka, K.

Orientation dependence of β1→ β1′ stress-induced martensitic transformation

in a Cu-AI-Ni alloy. Metallurgical Transactions A. 1988. 19(4): 915-923.

78. Eisenwasser, J. and Brown, L. Pseudoelasticity and the strain-memory effect

in Cu-Zn-Sn alloys. Metallurgical Transactions. 1972. 3(6): 1359-1363.

79. Lexcellent, C. Shape-Memory Alloys Handbook: Wiley. 2013.

80. Maki, T. Ferrous shape memory alloys. Shape Memory Materials. 1999: 117-

132.

81. Chakravorty, S. and Wayman, C. The thermoelastic martensitic

transformation inβ′ Ni-Al alloys: I. Crystallography and morphology.


82. Ishida, K., Kainuma, R., Ueno, N. and Nishizawa, T. Ductility enhancement

in NiAl (β2)-base alloys by microstructural control. Metallurgical

Transactions A. 1991. 22(2): 441-446.

83. He, Z.-R. and Zhou, J.-E. Comparative study of martensitic transformation

behavior of NiAlMn and NiAlMnFe high temperature shape memory alloys.

Materials Science and Engineering: A. 2003. 360(1): 183-190.

84. Donkersloot, H. and Van Vucht, J. Martensitic transformations in gold-

titanium, palladium-titanium and platinum-titanium alloys near the

equiatomic composition. Journal of the Less Common Metals. 1970. 20(2):

83-91.

85. N. F. Kennon and D. P. Dunne. Shape Strains Associated with Thermally-

Induced And Stress-Induced Martensite In A Cu-Al-Ni Shape Memory Alloy.

Acta Metall. 1982. 30: 429-435.

253

86. Chen, Y., Zhang, X., Dunand, D. C. and Schuh, C. A. Shape memory and

superelasticity in polycrystalline Cu–Al–Ni microwires. Applied Physics

Letters. 2009. 95(17): 171906.

87. Miyazaki, S and M. Fremond. Shape memory alloys. International Centre for

Mechanical Sciences: Springer. 1996.

88. Zhang Xiangyang, S. Q., Yu Shouwen A non-invariant plane model for the

interface in CuAlNi single crystal shape memory alloys. Journal of the

Mechanics and Physics of Solids. 2000. 48: 2163–2182.

89. Nó, M. L., Caillard, D. and San Juan, J. A TEM study of martensite habit

planes and orientation relationships in Cu–Al–Ni shape memory alloys using

a fast Δg-based method. Acta Materialia. 2009. 57(4): 1004-1014.

90. Qiao, L., Rimoli, J., Chen, Y., Schuh, C. and Radovitzky, R. Nonlocal

Superelastic Model of Size-Dependent Hardening and Dissipation in Single

Crystal Cu-Al-Ni Shape Memory Alloys. Physical Review Letters. 2011.

106(8).

91. Xu, J. W. Effects of Gd addition on microstructure and shape memory effect

of Cu–Zn–Al alloy. Journal of Alloys and Compounds. 2008. 448(1-2): 331-

335.

92. H. Morawiec, J. L., D. Stró ˙z, M. Gigla Structure and properties of melt-

spun Cu–Al–Ni shape memory alloys. Materials Science and Engineering A.

1999. 275: 708-712.

93. Castro, M. L. a. R. R. Isothermal decomposition of some β Cu-Zn-Al alloys

with e/a=1.48. Materials Science and Engineering A 1999. 273-275:: 577-

580.

94. Dvorack, M. A. a. H. C. Thermal diffuse scattering in β-phase CuAlNi alloy.

Scripta Metallurgica. 1983. 17: 131-134.

95. Zhang, S. Cu-based shape memory powder preparation using the mechanical

alloying technique. Materials Science and Engineering A. 1993. 171: 257-

262.

96. M. Morin, F. T. Influence of thermal cycling on the reversible martensitic

transformation in a Cu-A1-Ni shape memory alloy. Materials Science and

Engineering A. 1995. 196: 177-181.

97. Na, Wpływ Szybkości Obrotowej Bębna Chłodzącego, Formowanie Się

Tekstury W. Stopach Na, and Bazie. Effect of wheel velocity on texture

254

formation and shape memory in Cu-Al-Ni based melt-spun ribbons. Archives

of Metallurgy and Materials. 2009. 54(3).

98. Pelosin, V. and A. Rivière. Structural and mechanical spectroscopy study of

the β′1 martensite decomposition in Cu-12% Al-3% Ni(wt.%) alloy Journal

of Alloys and Compounds. 1998. 268((1-2)): 166-172.

99. Z.G. Wei, H.Y. Peng, D.Z. Yang, C.Y. Chung, J.K.L. Lai. Reverse

transformations in CuA1NiMnTi alloy at elevated temperatures. Acta

Materialia. 1996. 44(3): 1189-1199.

100. Pelosin, V. and Rivière, A. NiTi and CuAlNi Martensite Studied by

Isothermal Mechanical Spectroscopy. J. Phys. IV France. 1997. 07(C5): C5-

567-C565-572.

101. Recarte, V., Pérez-Sáez, R., Bocanegra, E., Nó, M. and San Juan, J.

Dependence of the martensitic transformation characteristics on

concentration in Cu–Al–Ni shape memory alloys. Materials Science and

Engineering: A. 1999. 273: 380-384.

102. Y. Itsumi, Y. M., T. Takashima, Kazuhito Kamei, Kazuko Sugimoto The

Effects of Ageing on the Martensitic Transformation Temperature in Cu-Al-

Ni-Mn-Ti Shape Memory Alloys. Advanced Materials Research. 1991. 56-

58: 469-474.

103. Karagoz, Z. and Canbay, C. A. Relationship between transformation

temperatures and alloying elements in Cu–Al–Ni shape memory alloys.

Journal of Thermal Analysis and Calorimetry. 2013. 114(3): 1069-1074.

104. Chang, S. H. Influence of chemical composition on the damping

characteristics of Cu–Al–Ni shape memory alloys. Materials Chemistry and

Physics. 2011. 125(3): 358-363.

105. Recarte, V., Pérez-Landazábal, J. I., Nó, M. L. and San Juan, J. Study by

resonant ultrasound spectroscopy of the elastic constants of the β phase in

Cu-Al-Ni shape memory alloys. Materials Science and Engineering: A. 2004.

370(1-2): 488-491.

106. Recarte, V., Perez-Landazabal, J. I., Gomez-Polo, C., Sanchez-Alarcos, V.,

Cesari, E. and Pons, J. Vibrational and magnetic contributions to the entropy

change associated with the martensitic transformation of Ni-Fe-Ga

ferromagnetic shape memory alloys. J Phys Condens Matter. 2010. 22(41):

416001.

255

107. Miyazaki, S., Otsuka, K., Sakamoto, H. and Shimizu, K. The fracture of Cu–

Al–Ni shape memory alloy. Transactions of the Japan Institute of Metals.

1981. 22(4): 244-252.

108. Dutkiewicz, J., Czeppe, T. and Morgiel, J. Effect of titanium on structure and

martensic transformation in rapidly solidified Cu–Al–Ni–Mn–Ti alloys.

Materials Science and Engineering: A. 1999. 273: 703-707.

109. Van Humbeeck J, ChandrsekaranM and Stalmans R. Copper-based shape

memory alloys and the martensitic transformation. Proc. Int. Conf. Mart.

Trans. 1993. 25: 1015.

110. Chen, C. and Liu, T. Phase transformations in a Cu-14.2 Al-7.8 Ni alloy.

Metallurgical and Materials Transactions A. 2003. 34(3): 503-509.

111. Chentouf, S. M., Bouabdallah, M., Gachon, J. C., Patoor, E. and Sari, A.

Microstructural and thermodynamic study of hypoeutectoidal Cu–Al–Ni

shape memory alloys. Journal of Alloys and Compounds. 2009. 470(1-2):

507-514.

112. Ratchev, P., J. Van Humbeeck, L. Delaey On the formation of 2H stacking

sequence in 18R martensite plates in a precipitate containing CuAlNiTiMn

alloy Acta Metallurgica Et Materialia. 1993. 41(8): 2441-2449.

113. V. Recarte, I. H., J. Herreros, M.L. Nó, J.San Juan Precipitation of the stable

phases in Cu-Al-Ni shape memory alloys. Scripta Materialia. 1996. 34: 255-

260.

114. Font, J., Muntasell, J., Pons, J. and Cesari, E. Thermal cycling effects in high

temperature Cu-Al-Ni-Mn-B shape memory alloys. Journal of materials

research. 1997. 12(9): 2288-2297.

115. Morris, M. A. Microstructural Influence on Ductility and Shape Memory

Effect of some Modified Cu.Ni.Ai Alloys. Scripta Metallugica. 1991. 25:

1409-1414.

116. Lojen, G., Anžel, I., Kneissl, A., Križman, A., Unterweger, E., Kosec, B. and

Bizjak, M. Microstructure of rapidly solidified Cu–Al–Ni shape memory

alloy ribbons. Journal of Materials Processing Technology. 2005. 162–

163(0): 220-229.

117. M. Fremond, S. M. Shape Memory Alloys, Wien, New York: Springer-

Verlag. 1996.

118. K. Otsuka, C. M. W. Shape Memory Materials. Cambridge University Press,

256

Cambridge. 1998.

119. S. Miyazaki, K. O., H. Sakamoto, K. Shimizu. Study of Fracture in Cu-

Al-Ni Shape Memory Bicrystals. Trans. Jpn. Inst. Met. . 1981. 22 244-252.

120. S.W. Husain, P. C. C. Grain boundary embrittlement in Cu-AI-Ni β phase

alloys. J. Mater. Sci. . 1987. 22 2351-2356.

121. Lee, J. S. and Wayman, C. M. Grain refinement of Cu-Zn-Al shape memory

alloys. Metallography. 1986. 19(4): 401-419.

122. G.N. Sure, L. C. B. The mechanical properties of grain refined β- Cu-Al-Ni

strain- Memory alloys. Metall. Trans. A 1984. 15 1613-1621.

123. Bhattacharya, S., Bhuniya, A. and Banerjee, M. K. Influence of minor

additions on characteristics of Cu-Al-Ni alloy. Materials Science and

Technology. 1993. 9(8): 654-658.

124. Adachi, K., Hamada, Y. and Tagawa, Y. Crystal structure of the X-phase in

grain-refined Cu-Al-Ni-Ti shape memory alloys. Scripta Metallurgica. 1987.

21(4): 453-458.

125. Kim, J., Roh, D., Lee, E. and Kim, Y. Effects on microstructure and tensile

properties of a zirconium addition to a Cu-Al-Ni shape memory alloy.

Metallurgical and Materials Transactions A. 1990. 21(2): 741-744.

126. Morris, M. A. and Lipe, T. Microstructural influence of Mn additions on

thermoelastic and pseudoelastic properties of Cu-Al-Ni alloys. Acta

Metallurgica et Materialia. 1994. 42(5): 1583-1594.

127. Gao, Y., Zhu, M. and Lai, J. K. L. Microstructure characterization and effect

of thermal cycling and ageing on vanadium-doped Cu–Al–Ni–Mn high-

temperature shape memory alloy. Journal of Materials Science. 1998. 33(14):

3579-3584.

128. Adachi, K., Shoji, K. and Hamada, Y. Formation of (X) Phases and Origin of

Grain Refinement Effect in Cu-Al-Ni Shape Memory Alloys Added with

Titamium. ISIJ International. 1989. 29(5): 378-387.

129. Vajpai, S. K., Dube, R. K. and Sangal, S. Microstructure and properties of

Cu-Al-Ni shape memory alloy strips prepared via hot densification rolling of

argon atomized powder preforms. Materials Science and Engineering A.

2011. 529(1): 378-387.

130. Zhu, M., Ye, X., Li, C., Song, G. and Zhai, Q. ChemInform Abstract:

Preparation of Single Crystal CuAlNiBe SMA and Its Performances.

257

ChemInform. 2009. 40(34): no-no.

131. Morris, M. A. and S. Gunter. Effect of heat treatment and thermal cycling on

transformation temperatures of ductile Cu-Al-Ni-Mn-B alloys. Scripta

Metallurgica et Materiala. 1992. 26(11): 1663-1668.

132. D. W. Roh, J.W.K., T.J.Cho, Y. G. Kim Tensile properties and

microstructure of microalloyed Cu-A1-Ni-X shape memory alloys. Materials

Science and Engineering: A. 1991. 136: 17-23.

133. Khan, A. and Delaey, L. The Effect of Grain Size on the Strength of Cu-Al

Beta'-Martensite. Z Metallkd. 1969. 60(12): 949-951.

134. Xu, H., Zhu, M., Song, G., Mao, X. And Li, C. A. Study on Shape Memory

Performance of Single Crystal Cu-Al-Ni-Be Alloy [J]. Materials Review.

2008. 4: 036.

135. Xu, H. P., Song, G. F. and Mao, X. M. Influence of Be and Ni to Cu-Al Alloy

Shape Memory Performance. Advanced Materials Research. 2011. 197:

1258-1262.

136. Gomes, R. M., Veloso, A. C. R., Buono, V. T. L., Lima, S. J. G. and Melo, T.

A. A. Pseudoelasticity of Cu-13.8Al-Ni Alloys Containing V and Nb.

Advances in Science and Technology. 2008. 59: 101-107.

137. Zhu, M., Ye, X., Li, C., Song, G. and Zhai, Q. Preparation of single crystal

CuAlNiBe SMA and its performances. Journal of Alloys and Compounds.

2009. 478(1): 404-410.

138. F. Dagdelen, T. G., A. Aydogdu, Y. Aydogdu, O. Adigu zel Effects of

thermal treatments on transformation behaviour in shape memory Cu–Al–Ni

alloys. Materials Letters. 2003. 57: 1079-1085.

139. Van Humbeeck, J., Van Hulle, D. and Delacey, L. A Two-Stage Martensite

Transformation in a Cu-13. 99 mass% Al-3. 5 mass% Ni Alloy. Trans. Jpn.

Inst. Met. 1987. 28(5): 383-391.

140. Picornell, C., Pons, J. and Cesari, E. Effects of Thermal Ageing in, B-Phase

in Cu-Al-Ni Single Crystals. Journal de Physique-Colloques. 1997. 7(5): 323-

328.

141. Gastien, R., Corbellani, C., Sade, M. and Lovey, F. Thermal and

pseudoelastic cycling in Cu–14.1 Al–4.2 Ni (wt%) single crystals. Acta

materialia. 2005. 53(6): 1685-1691.

142. Wang, Z., Liu, X. F. and Xie, J. X. Effect of γ2 phase evolution on

258

mechanical properties of continuous columnar-grained Cu–Al–Ni alloy.

Materials Science and Engineering: A. 2012. 532: 536-542.

143. Suresh, N. and Ramamurty, U. The effect of ageing on the damping

properties of Cu–Al–Ni shape memory alloys. Smart materials and structures.

2005. 14(5): N47.

144. Cheniti, H., Bouabdallah, M. and Patoor, E. High temperature decomposition

of the β1 phase in a Cu–Al–Ni shape memory alloy. Journal of Alloys and

Compounds. 2009. 476(1-2): 420-424.

145. Balo, Ş. N. and Sel, N. Effects of thermal aging on transformation

temperatures and some physical parameters of Cu–13.5wt.%Al–4wt.%Ni

shape memory alloy. Thermochimica Acta. 2012. 536: 1-5.

146. Wei, Z., Peng, H., Zou, W. and Yang, D. Aging effects in a Cu-12Al-5Ni-

2Mn-1Ti shape memory alloy. Metallurgical and Materials Transactions A.

1997. 28(4): 955-967.

147. Singh, J. C., H.; Wayman, C.M. Transformation Sequence in a Cu-Al-Ni

Shape Memory Alloy at Elevated Temperatures. Metallurgical transactions.

A. 1986. 17 A(1): 65-72.

148. Singh, J. C., H.; Wayman, C.M Precipitation behavior of a CuAlNi shape

memory alloy at elevated temperatures" Scripta Metallurgica. 1985. 19(2):

231-234.

149. P. Rodriguez and G. Guenin. Thermal Aging Behaviour and Origin of a Cu-

Al-Ni Shape Memory Alloy. Materials Science and Engineering A. 1990.

129: 273-277.

150. Kuwano, N. and C. M. Wayman. Some Effects of Parent Phase Aging on the

Martensitic Transformation in A Cu-Al-Ni Shape Memory Alloy.

Metallurgical transactions. A, Physical Metallurgy and Materials Science.

1984. 15 A(4): 621-626.

151. Zárubová, N., Gemperlová, J., Gärtnerová, V. and Gemperle, A. Stress-

induced martensitic transformations in a Cu–Al–Ni shape memory alloy

studied by in situ transmission electron microscopy. Materials Science and

Engineering: A. 2008. 481-482: 457-461.

152. Zarubova, N., Gemperle, A. and Novak, V. Initial stages of γ2 precipitation in

an aged Cu-Al-Ni shape memory alloy. Materials Science and Engineering:

A. 1997. 222(2): 166-174.

259

153. Sakamoto, H., Sugimoto, K., Nakamura, Y., Tanaka, A. and Shimizu, K. i.

Martensite phase causing two way shape memory effect in Cu-13. 7 Al-4. 0

Ni(mass%) alloy single crystals. Mater. Trans., JIM(Japan). 1991. 32(2): 128-

134.

154. Sari, U., Kirindi, T., Ozcan, F. and Dikici, M Effects of aging on the

microstructure of a Cu-Al-Ni-Mn shape memory alloy. International Journal

of Minerals Metallurgy and Materials,. 2011. 18(4): 430-436.

155. Zarubova, N., Gemperle, A. and Novak, V. Ageing Phenornena in a Cu-Al-

Ni Alloy. Le Journal de Physique IV. 1997. 7(C5): C5-281-C285-286.

156. Morawiec, H. and Gigla, M. Effect of ageing on shape recovery in CuAlNi

alloy with Ti + B additions. Acta Metallurgica et Materialia. 1994. 42(8):

2683-2686.

157. N. F. Kennon and D. P. Dunne. Thermal Aging Behaviour and Origin of a

Cu-Al-Ni Shape Memory Alloy. Materials Science and Engineering: A. 1990.

129: 273-277.

158. Daricek, T., Lasek, J., Zarubova, N., Novak, V. and Bartuska, P. Composites

and Cu based shape memory alloys-Ageing effects in a Cu-Al-Ni shape

memory alloy. Journal de Physique-Colloques. 2001. 11(8): 179-184.

159. C. Picornell, J. Pons, E. Cesari. Cesari Mechanical stabilisation and

anomalous behaviour of the stress–strain loops in Cu–Al–Ni single crystals.

Scripta Materialia. 2006. 54: 459-463.

160. Picornell, C., Pons, J. and Cesari, E. Stress–temperature relationship in Cu–

Al–Ni single crystals in compression mode. Materials Science and

Engineering: A. 2004. 378(1): 222-226.

161. Aydogdu, A., Aydogdu, Y., Adigüzel, O. The influence of aging pn the

martensite ordering and stabilization in shape memory Cu-Al-Ni alloys.

Materials research bultetin 1997. 32: 507-513.

162. Aydogdu, A., Aydogdu, Y., Adigüzel, O. Improvement of Hardness and

Microstructures by Ageing in Shape Memory CuAlNi Alloys. Le Journal de

Physique IV. 1997. 07(C5): C5-311-C315-316.

163. Aksu Canbay, C. and Aydoğdu, A. Thermal analysis of Cu-14.82 wt% Al-

0.4 wt% Be shape memory alloy. Journal of Thermal Analysis and

Calorimetry. 2013. 113(2): 731-737.

260

164. Hondros, E. and Seah, M. Segregation to interfaces. International Metals

Reviews. 1977. 22(1): 262-301.

165. Stein, D., Johnson, W., White, C., Chadwick, G. and Smith, D. Grain

Boundary Structure and Properties. Academic Press, New York. 1976.

166.

Ni shape memory alloys. Scripta metallurgica et materialia. 1991. 25(4): 883-

888.

167. Leu, S., Chen, Y. and Jean, R. Effect of rapid solidification on mechanical

properties of Cu-Al-Ni shape memory alloys. Journal of materials science.

1992. 27(10): 2792-2798.

168. Hodgson, D., Wu, MH, Biermann, RJ Metals Handbook. ASM International,

Ohio. 1990. 2: 897.

169. Gall, K., Yakacki, C. M., Liu, Y., Shandas, R., Willett, N. and Anseth, K. S.

Thermomechanics of the shape memory effect in polymers for biomedical

applications. Journal of Biomedical Materials Research Part A. 2005. 73(3):

339-348.

170. Stöckel, D. The shape memory effect: phenomenon, alloys, applications. 报

告 (2000 年), NDC, Nitinol Devices & Components 公司, 美国加利福尼亚

州 Fremont, www. nitinol-europe. com/pdfs/smemory. pdf (2007 年 12 月 24

日浏览). 2000.

171. Leo, D. J., Weddle, C., Naganathan, G. and Buckley, S. J. Vehicular

applications of smart material systems. Proceedings of the 5th Annual

International Symposium on Smart Structures and Materials: International

Society for Optics and Photonics. 106-116.

172. Stoeckel, D. Shape memory actuators for automotive applications. Materials

& Design. 1990. 11(6): 302-307.

173. Wilkes, K. E. and Liaw, P. K. The fatigue behavior of shape-memory alloys.

JOM. 2000. 52(10): 45-51.

174. Hornbogen, E. Review Thermo-mechanical fatigue of shape memory alloys.

Journal of materials science. 2004. 39(2): 385-399.

175. Widdle, R. D., Grimshaw, M. T., Crosson-Elturan, K. S., Mabe, J. H.,

Calkins, F. T., Gravatt, L. M. and Shome, M. High stiffness shape memory

alloy actuated aerostructure. Google Patents. 2013.

261

176. Mani, R., Lagoudas, D. C. and Rediniotis, O. K. MEMS-based active skin for

turbulent drag reduction. Proceedings of the Smart Structures and Materials:

International Society for Optics and Photonics. 9-20.

177. Tawfik, M., Ro, J.-J. and Mei, C. Thermal post-buckling and aeroelastic

behaviour of shape memory alloy reinforced plates. Smart Materials and

Structures. 2002. 11(2): 297.

178. Furuya, Y. and Shimada, H. Shape memory actuators for robotic applications.

Materials & Design. 1991. 12(1): 21-28.

179. Wu, M. H. and Schetky, L. Industrial applications for shape memory alloys.

Proceedings of the Proceedings of the International Conference on Shape

Memory and Superelastic Technologies, Pacific Grove, California.

180. Russell, S. M. SMST-2000: Proceedings of the International Conference on

Shape Memory and Superelastic Technologies: SMST, the International

Organization on Shape Memory and Superelastic Technology. 2001.

181. Sari, U. Influences of 2.5wt% Mn addition on the microstructure and

mechanical properties of Cu-Al-Ni shape memory alloys. International

Journal of Minerals, Metallurgy, and Materials. 2010. 17(2): 192-198.

182. Tarhan, E. F. Aging Characteristics of Copper based Shape Memory Alloys.

Middle East Technical University; 2004.

183. Imran Khan, M., Kim, H. Y., Nam, T.-h. and Miyazaki, S. Formation of

nanoscaled precipitates and their effects on the high-temperature shape-

memory characteristics of a Ti50Ni15Pd5Cu10 alloy. Acta Materialia. 2012.

60(16): 5900-5913.

184. Kumar, M. and Gupta, R. Introduction to Shape Memory Alloys: Springer.

2008.

185. Bergeon, N., Guenin, G. and Esnouf, C. Study of the Faults Stackings in the

γ(f.c.c.)-ε(h.c.p.) Martensitic Transformation. J. Phys. IV France. 1997.

07(C5): C5-125-C125-130.

186. Putaux, J. L. and Chevalier, J. P. HREM study of self-accommodated thermal

ε-martensite in an FeMnSiCrNi shape memory alloy. Acta Materialia. 1996.

44(4): 1701-1716.

187. Eskil, M. and Kayali, N. X-ray analysis of some shape memory CuZnAl

alloys due to the cooling rate effect. Materials Letters. 2006. 60(5): 630-634.

188. Yildirim Aydogdu, A. A., Osman Adiguzel Self-accommodating martensite

262

plate variants in shape memory CuAlNi alloys. Journal of Materials

Processing Technology. 2002. 123: 498-500.

189. Friend, C. M. The effect of aluminium content on the martensite phase

stabilities in metastable CuAlNi alloys. Scripta Metallurgica. 1989. 23(10):

1817-1820.

190. M. Miki, Y. O., Y. Hiramatsu effects of B and Cr additions on the grain

refinement and ductility of a Cu-14Al-3Ni shape memory alloy. Nippon

Kinzoku Gakkai-si. 1987. 51(9): 815-823.

191. M. O. Lai, L. Lu, W. H. Lee. Influence of heat treatment on properties of

copper-based shape-memory alloy. Journal of Materials Science. 1996. 31:

1537-1543.

192. Fernández, J., Benedetti, A. V., Guilemany, J. M. and Zhang, X. M. Thermal

stability of the martensitic transformation of Cu–Al–Ni–Mn–Ti. Materials

Science and Engineering: A. 2006. 438-440: 723-725.

193. Sutou, Y., Omori, T., Koeda, N., Kainuma, R. and Ishida, K. Effects of grain

size and texture on damping properties of Cu–Al–Mn-based shape memory

alloys. Materials Science and Engineering: A. 2006. 438-440: 743-746.

194. Mallik, U. S. and Sampath, V. Influence of aluminum and manganese

concentration on the shape memory characteristics of Cu–Al–Mn shape

memory alloys. Journal of Alloys and Compounds. 2008. 459(1-2): 142-147.

195. Q. Xuan, J. B., T.Y. Hsu The effect of martensite ordering on shape memory

effect in a copper–zinc–aluminium alloy. Mater. Sci. Eng. 1987. 93: 205-211.

196. Salzbrenner, R. J. a. C., M. On the thermodynamics of thermoelastic

martensitic transformations. Acta Metallurgica. 1979. 27(5): 739-748.

197. Adigüzel, O. Martensite ordering and stabilization in copper based shape

memory alloys. Materials research bulletin. 1995. 30(6): 755-760.

198. Aydogdu, A., Aydogdu, Y. and Adiguzel, O. Long-term ageing behaviour of

martensite in shape memory Cu–Al–Ni alloys. Journal of materials

processing technology. 2004. 153: 164-169.

199. Zhang, X., Brinson, L. and Sun, Q.-P. The variant selection criteria in single-

crystal CuAlNi shape memory alloys. Smart materials and structures. 2000.

9(5): 571.

200. Tatar, C. Gamma irradiation-induced evolution of the transformation

temperatures and thermodynamic parameters in a CuZnAl shape memory

263

alloy. Thermochim. Acta. 2005. 437: 121-125.

201. Ortín, J. and Planes, A.. Thermodynamics of thermoelastic martensitic

transformations. Acta Metallurgica. 1989. 37(5): 1433-1441.

202. Huang, W. M., Wu, J. A., Lim, B. Y. And Vahhi, I. Behaviour of Young‟s

Modulus in Shape Memory Alloys upon Mechanical Loading. Mater Sci

ISSN. 2005: 1392-1320.

203. Motoyasu, G., Kaneko, M., Soda, H. and McLean, A. Continuously cast Cu-

Al-Ni shape memory wires with a unidirectional morphology. Metallurgical

and Materials Transactions A. 2001. 32(3): 585-593.

204. Lee, J. and Wayman, C. Grain refinement of a Cu-Al-Ni shape memory alloy

by Ti and Zr additions. Trans Jpn Inst Met. 1986. 27(8): 584-591.

205. Yang, N., Laird, C. and Pope, D. P. The cyclic stress-strain response of

polycrystalline, pseudoelastic Cu-14.5 wt pct Al-3 wt pct Ni alloy.


206. Funakubo, H. Shape Memory Alloys: C R C Press LLC. 1987.

207. Shimizu, K. and Otsuka, K. Optical and electron microscope observations of

transformation and deformation characteristics in Cu-Al-Ni marmem alloys.

Shape Memory Effects in Alloys: Springer. 59-87; 1975.

208. Suezawa, M. and Sumino, K. Lattice distortion and the effective shear

modulus along a coherent twin boundary. physica status solidi (a). 1976.

36(1): 263-268.

209. Izadinia, M. and Dehghani, K. Structure and properties of nanostructured Cu-

13.2Al-5.1Ni shape memory alloy produced by melt spinning. Transactions

of Nonferrous Metals Society of China. 2011. 21(9): 2037-2043.

210. Bhattacharya, K. Microstructure of Martensite: Why it Forms and how it

Gives Rise to the Shape-memory Effect: OUP Oxford. 2003.

211. Churchill, C. B., Shaw, J. A. and Iadicola, M. A. Tips and tricks for

characterizing shape memory alloy wire: Part 3-localization and propagation

phenomena. Experimental Techniques. 2009. 33(5): 70-78.

212. I. Hurtado, P. R., J. Van Humbeeck and L. Delaey A fundamental study of

the X-phase preciptation in Cu-Al-Ni-Ti-(Mn) shape memory alloys. Acta

Materialia. 1995. 44: 3299-3306.

213. Lee, JS and Wayman, CM. Grain Refinement of a Cu–Al–Ni Shape Memory

264

Alloy by Ti and Zr Additions. Transactions of the Japan Institute of Metals. 1986.

27(8): 584-591.

214. Sure, G. N. B., L. C. The mechanical properties of grain refined β- cuaini

strain-memory alloys. Metallurgical Transactions A. 1984. 15(8): 1613-1621.

215. Malarría, J., Elgoyhen, C., Vermaut, P., Ochin, P. and Portier, R. Shape

memory properties of Cu-based thin tapes obtained by rapid solidification

methods. Materials Science and Engineering: A. 2006. 438-440: 763-767.

216. Dutkiewicz, J., Pons, J. and Cesari, E. Effect of γ precipitates on the

martensitic transformation in Cu-Al-Mn alloys. Materials Science and

Engineering: A. 1992. 158(1): 119-128.

217. Cullity, B. D. Elements of X-Ray Diffraction: Addison-Wesley Publishing

Company. 1978.

218. Yang, G.-S., Lee, J.-K. and Jang, W.-Y. Effect of grain refinement on phase

transformation behavior and mechanical properties of Cu-based alloy.

Transactions of Nonferrous Metals Society of China. 2009. 19(4): 979-983.

219. Aydogdu, A., Aydogdu, Y. and Adiguzel, O. Long-term ageing behaviour of

martensite in shape memory Cu–Al–Ni alloys. Journal of Materials

Processing Technology. 2004. 153-154: 164-169.

220. Saiji Matsuoka, M. H., Ryuichiro Oshima and Francisco Eiichi Fujita

Improvement of Ductility of Melt Spun Cu-Al-Ni Shape Memory Alloy

Ribbons by Addition of Ti or Zr

Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and

Review Papers. 1983. 22(Part 2, No. 8): 528-530.

221. Matsuoka, S., Hasebe, M., Oshima, R. and Fujita, F. E. Improvement of

ductility of melt spun Cu-Al-Ni shape memory alloy ribbons by addition of

Ti or Zr. Japanese Journal of Applied Physics. 1983. 22(8): L528-L530.

222. Yang, Q. P., Sun, L. and Feng, Y. Z. Experiment of Beam Crack Repair

Using Shape Memory Alloy. Applied Mechanics and Materials. 2011. 71-78:

1707-1710.

223. Gollerthan, S., Young, M., Baruj, A., Frenzel, J., Schmahl, W. and Eggeler,

G. Fracture mechanics and microstructure in NiTi shape memory alloys. Acta

Materialia. 2009. 57(4): 1015-1025.

224. Wycech, J. S. Influencing parameters on the fracture resistance of aluminum

alloys. Massachusetts Institute of Technology; 1971.

265

225. Sarı, U. and Aksoy, İ. Electron microscopy study of 2H and 18R martensites

in Cu–11.92wt% Al–3.78wt% Ni shape memory alloy. Journal of Alloys and

Compounds. 2006. 417(1-2): 138-142.

226. Morawiec, H., Ilczuk, J., Stróz, D., Goryczka, T. and Chrobak, D. Two-stage

martensitic transformation in NiTi alloys caused by stress fields. Le Journal

de Physique IV. 1997. 7(C5): C5-155-C155-159.

227. Yang, S., Liu, Y., Wang, C. and Liu, X. Martensite stabilization and thermal

cycling stability of two-phase NiMnGa-based high-temperature shape

memory alloys. Acta Materialia. 2012. 60(10): 4255-4267.

228. Font, J., Cesari, E., Muntasell, J. and Pons, J. Thermomechanical cycling in

Cu–Al–Ni-based melt-spun shape-memory ribbons. Materials Science and

Engineering: A. 2003. 354(1-2): 207-211.

229. Picornell, C., Pons, J. and Cesari, E. Effects of thermal ageing in β-phase in

Cu-Al-Ni single crystals. Le Journal de Physique IV. 1997. 7(C5): C5-323-

C325-328.

230. Daricek, T., Lasek, J., Zarubova, N., Novak, V. and Bartuska, P. Ageing

effects in a Cu-Al-Ni shape memory alloy. Le Journal de Physique IV. 2001.

11(PR8): Pr8-179-Pr178-184.

231. Tarhan, E. F. Aging Characteristics of Copper based Shape Memory Alloys.

Middle East Technical University; 2004.

232. Roh*, D. W., Kim, J. W., Cho, T. J. and Kim, Y. G. Tensile properties and

microstructure of microalloyed Cu-A1-Ni-X shape memory alloys. Materials

Science and Engineering: A. 1991. 136: 17-23.

233. Leslie, W. C. The physical metallurgy of steels: Hempisphere Pub. Corp.

1981.

234. Kennon, N. F., Dunne, D. P. and Middleton, L. Aging Effects in Copper-

Based Shape Memory Alloys. Metallurgical Transactions A. 1982. 13(4):

551-555.

235. Dogan, E. CoNiGa High Temperature Shape Memory Alloys. Texas A&M

University; 2010.

236. Otsuka, K. and Ren, X. Recent developments in the research of shape

memory alloys. Intermetallics. 1999. 7(5): 511-528.

237. Ma, Y., Yang, S., Wang, C. and Liu, X. Tensile characteristics and shape

memory effect of Ni56Mn21Co4Ga19 high-temperature shape memory alloy.

266

Scripta Materialia. 2008. 58(10): 918-921.

238. Yang, J. P. and Kim, Y. G. Tensile properties and shape memory effect of

chromium-varied Fe-30Mn-5Si-Cr shape memory alloys. Materials Science

and Engineering: A. 1992. 154(1): L1-L3.

239. Duerig, T. and Pelton, A. Ti-Ni shape memory alloys. Materials properties

handbook: Titanium alloys. 1994: 1035-1048.

240. Ma, Y., Yang, S., Liu, Y. and Liu, X. The ductility and shape-memory

properties of Ni–Mn–Co–Ga high-temperature shape-memory alloys. Acta

Materialia. 2009. 57(11): 3232-3241.

241. Gao, Y., Zhu, M. and Lai, J. Microstructure characterization and effect of

thermal cycling and ageing on vanadium-doped Cu–Al–Ni–Mn high-

temperature shape memory alloy. Journal of materials science. 1998. 33(14):

3579-3584.

242. Lin, B., Gall, K., Maier, H. J. and Waldron, R. Structure and

thermomechanical behavior of NiTiPt shape memory alloy wires. Acta

biomaterialia. 2009. 5(1): 257-267.

243. Wu, S., Lin, H. and Chen, S. Phenomenological analysis of martensitic

transformation in cold-rolled TiNi-base shape memory alloys. Materials

chemistry and physics. 2001. 68(1): 149-156.

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5 INFLUENCE OF ALLOYING ELEMENTS AND AGING TREATMENT …eprints.utm.my/id/eprint/77887/1/SafaaNajahSaudPFKM2014.pdf · v ABSTRACT Nickel-Titanium (Ni Ti) shape memory alloys (SMAs)