Magnesium and Its Alloys as Implant Materials

Mirco Peron earned his degree in mechanical engineering (summa cum laude) in 2015 from the University of Padova, where his thesis evaluated the fatigue damage and stiffness evolution in composite laminates. He is currently a PhD student at Norwegian University of Science and Technology (NTNU), Trondheim. His PhD topic deals with the optimization of mechanical and corrosion properties of magnesium and its alloys for biomedical applications, with particular reference to the corrosion-assisted cracking phenomena. Filippo Berto is Chair of Structural Integrity at the Norwegian University of Science and Technology in Norway. He is in charge of the Mechanical and Material Characterization Lab in the Department of Mechanical and Industrial Engineering. He is author of more than 500 technical papers, mainly oriented to materials science engineering, the brittle failure of different materials, notch effect, the application of the finite element method to the structural analysis, the mechanical behavior of metallic materials, the fatigue performance of notched components as well as the reliability of welded, bolted and bonded joints. Since 2003, he has been working on different aspects of the structural integrity discipline, by mainly focusing attention on problems related to the static and fatigue assessment of engineering materials with particular attention to biomedical and medical applications and materials. Jan Torgersen is Professor of mechanical engineering at NTNU, Trondheim. He received his PhD from Vienna University of Technology, where he worked on high-resolution laser microfabrication of hydrogels for tissue engineering. He was pioneering in the work of processing hydrogel formulations at micron scale resolution in vivo, in the presence of living cells and whole organisms. He received a postdoctoral fellowship to work on a nanoscale vapor deposition technique called atomic layer deposition, allowing conformal coating of thermally fragile and nanostructured substrates with atomically thin layers of a wide range of materials. He contributed to the development of a selflimiting deposition process for high-k materials for Dynamic Random Access Memory (DRAM) applications. His current research interests are micro- and nanofabrication as well as surface functionalization, with particular focus on biomedical applications.

Contents

List of Abbreviations ........................................................................................ ix

Authors........................................................................................................... xiii

Chapter 1 Introduction................................................................................... 1

1.1 Introduction ...........................................................................1

References.......................................................................................4

Chapter 2 Challenges and Common Strategies ............................................... 9

2.1 Introduction ...........................................................................9

2.2 Corrosion Mitigation Strategies..............................................9

2.2.1 Impurities Removal.................................................. 10

2.2.2 Alloying ................................................................... 11

2.2.3 Grain Size Modification........................................... 11

2.3 Mechanical Properties Tuning .............................................. 14

2.3.1 Grain Refinement .................................................... 15

2.3.2 Solid Solution Strengthening ................................... 16

2.3.3 Precipitation Hardening........................................... 16

2.4 Interplay among Mechanical Properties, Corrosion

Resistance and Biocompatibility........................................... 17

References..................................................................................... 17

Chapter 3 Synopsis of Properties of Biocompatible Mg and Its Alloys......... 21

3.1 Introduction ......................................................................... 21

3.2 High-Pure Magnesium.......................................................... 21

3.2.1 High-Pure Magnesium: Mechanical Properties........ 21

3.2.2 High-Pure Magnesium: Corrosion Resistance.......... 23

3.2.3 High-Pure Magnesium: Biocompatibility................. 24

3.3 Aluminum-Based Alloys ....................................................... 26

3.3.1 AZ Alloys ................................................................ 28

3.3.1.1 AZ Alloys: Mechanical Properties ............. 28

3.3.1.2 AZ Alloys: Corrosion Resistance ............... 30

3.3.1.3 AZ Alloys: Biocompatibility ...................... 33

3.3.2 AM Alloys ............................................................... 33

3.3.2.1 AM Alloys: Mechanical Properties ............ 35

3.3.2.2 AM Alloys: Corrosion Resistance .............. 36

3.3.2.3 AM Alloys: Biocompatibility ..................... 39

3.3.3 Mg–Al–RE Alloys ................................................... 39

3.3.3.1 Mg–Al–RE Alloys: Mechanical

Properties ................................................... 40

3.3.3.2 Mg–Al–RE Alloys: Corrosion

Resistance .................................................. 42

3.3.3.3 Mg–Al–RE Alloys: Biocompatibility ......... 44

3.4 Mg–Zn Alloys....................................................................... 45

3.4.1 Mg–Zn Binary Alloys .............................................. 46

3.4.1.1 Mg–Zn Binary Alloys: Mechanical

Properties ................................................... 47

3.4.1.2 Mg–Zn Binary Alloys: Corrosion

Resistance .................................................. 47

3.4.1.3 Mg–Zn Binary Alloys: Biocompatibility .... 49

3.4.2 Mg–Zn–Zr Alloys .................................................... 53

3.4.2.1 Mg–Zn–Zr Alloys: Mechanical

Properties ................................................... 53

3.4.2.2 Mg–Zn–Zr Alloys: Corrosion

Resistance .................................................. 54

3.4.2.3 Mg–Zn–Zr Alloys: Biocompatibility .......... 59

3.4.3 Mg–Zn–Ca Alloys ................................................... 62

3.4.3.1 Mg–Zn–Ca Alloys: Mechanical

Properties ................................................... 63

3.4.3.2 Mg–Zn–Ca Alloys: Corrosion

Resistance .................................................. 66

3.4.3.3 Mg–Zn–Ca Alloys: Biocompatibility ......... 67

3.4.4 Mg–Zn–Ca BMGs................................................... 68

3.4.4.1 Mg–Zn–Ca BMGs: Mechanical

Properties ................................................... 70

3.4.4.2 Mg–Zn–Ca BMGs: Corrosion Resistance.. 71

3.4.4.3 Mg–Zn–Ca BMGs: Biocompatibility......... 72

3.4.5 Mg–Zn–Mn Alloys .................................................. 73

3.4.5.1 Mg–Zn–Mn Alloys: Mechanical

Properties ................................................... 75

3.4.5.2 Mg–Zn–Mn Alloys: Corrosion

Resistance .................................................. 78

3.4.5.3 Mg–Zn–Mn Alloys: Biocompatibility ........ 82

3.4.6 Mg–Zn–RE Alloys................................................... 83

3.4.6.1 Mg–Zn–RE Alloys: Mechanical

Properties ................................................... 86

3.4.6.2 Mg–Zn–RE Alloys: Corrosion

Resistance .................................................. 88

3.4.6.3 Mg–Zn–RE Alloys: Biocompatibility......... 91

3.5 Mg–Ca Alloys....................................................................... 91

3.5.1 Mg–Ca Alloys: Mechanical Properties..................... 92

3.5.2 Mg–Ca Alloys: Corrosion Resistance ...................... 98

3.5.3 Mg–Ca Alloys: Biocompatibility............................ 101

3.6 Mg–RE Alloys.................................................................... 102

3.6.1 Mg–RE Alloys: Mechanical Properties .................. 106

3.6.2 Mg–RE Alloys: Corrosion Resistance.................... 108

3.6.3 Mg–RE Alloys: Biocompatibility........................... 112

References................................................................................... 116

Chapter 4 Tackling the Challenges ............................................................. 145

4.1 Introduction ....................................................................... 145

4.2 Radar Chart: An Easy Tool to Compare Corrosion,

Mechanical and Biological Performances ........................... 145

Reference .................................................................................... 147

Chapter 5 Outlook...................................................................................... 149

Reference .................................................................................... 149

Appendix A: Corrosion ................................................................................... 151

Appendix B: In Vitro Biocompatibility Assessment ......................................... 161

Index.............................................................................................................. 165