Corrosion Resistance of Aluminum and Magnesium Alloys: Understanding, Performance, and Testing

744 Pages·2010·6.56 MB·English

by  Edward Ghali

Corrosion Resistance of
Aluminum and
Magnesium Alloys
Understanding, Performance,
and Testing
Edward Ghali

Corrosion Resistance of
Aluminum and
Magnesium Alloys
WILEY SERIES IN CORROSION
R. Winston Revie, Series Editor
Corrosion Inspectionand Monitoring. Pierre R. Roberge
Corrosion Resistance ofAluminum and Magnesium Alloys:Understanding,
Performance, and Testing. EdwardGhali
Microbiologically Influenced Corrosion. Brenda J. Little andJason S. Lee
Corrosion Resistance ofAluminum and magnesium Alloys. Edward Ghali
Corrosion Resistance of
Aluminum and
Magnesium Alloys
Understanding, Performance,
and Testing
Edward Ghali
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LibraryofCongressCataloging-in-PublicationData:
Ghali,Edward.
Corrosionresistanceofaluminumandmagnesiumalloys:understanding,performance,and
testing/EdwardGhali.
p.cm.
Includesindex.
ISBN978-0-471-71576-4(cloth)
1. Aluminumalloys–Corrosion.2. Magnesiumalloys–Corrosion.3. Corrosionandanti-corrosives.
I. Title.
TA480.A6G452010
620.108623–dc22
2009014010
PrintedintheUnitedStatesofAmerica
10 9 8 7 6 5 4 3 2 1
I am grateful to my wife, Helen, whose unfailing encouragement and
support sustained me through the challenge of writing this book. There are
no words that can express my heartfelt gratitude to members of my close
happy family, in particular, Rafik and Sonia Ghali and their spouses,
Isabelle Coˆt(cid:2)e and Dominique Julien, who encouraged me enormously
during the realization of this book.

Contents
Preface xix 1.6.3. TheoryofMoreConcentrated
Solutions 17
Acknowledgments xxi 1.6.4. ElectrolyticConduction 19
1.7. Mobility ofIons 19
1.7.1. LawofAdditivityof
Kohlrausch 20
1.7.2. IonTransportNumber
Part One Electrochemical Fundamentals orIndex 21
and Active–PassiveCorrosionBehaviors 1.8. Conductance 23
1.9. Potential ofDecomposition 24
1. Fundamentals ofElectrochemical C. The Different Types
Corrosion 3 ofElectrodes 24
1.10. Gas Electrodes 24
Overview 3 1.11. Metal–Metal Ion Electrodes 25
1.11.1. AlloyedElectrodes 25
A. Thermodynamic Considerations 1.12. Metal–InsolubleSalt orOxide
ofCorrosion 3 Electrodes 26
1.1. Electrolytic Conductance 4 1.12.1. Metal–InsolubleSalt
Electrodes 26
1.1.1. FaradayLaws 5
1.12.2. Metal–InsolubleOxide
1.2. TendencytoCorrosion 6
Electrodes 27
1.3. The ElectrochemicalInterface 7
1.13. Electrodes of
1.3.1. ElectricDoubleLayer 8
Oxidation–Reduction 28
1.3.2. EquivalentCircuitoftheElectric
DoubleLayer 9 1.14. SelectiveIonElectrodes 29
1.4. Nernst Equation 9 1.14.1. GlassElectrodes 29
1.5. Standard Potentials of 1.14.2. CopperIon-Selective
Electrodes 30
Electrodes 12
1.5.1. StandardStatesin D. Electrochemical andCorrosion
Solution 12
Cells 31
1.5.2. HydrogenElectrode 13
1.15. ChemicalCells 31
1.5.3. PositiveandNegativeSignsof
1.15.1. ChemicalCellwith
Potentials 13
Transport 31
1.5.4. GraphicalPresentation 14
1.15.2. ChemicalCellWithout
Transport 33
B. Activity and Conductanceof the 1.16. Concentration Cells 34
Electrolyte 14 1.16.1. ConcentrationCellwith
1.6. Activity ofthe Electrolyte 14 DifferenceofActivity
1.6.1. ConstantandDegree attheElectrodeand
ofDissociation 14 Electrolyte 35
1.6.2. Activityand 1.16.2. JunctionPotential 37
Concentration 16 1.17. SolventCorrosionCells 41
vii