Corrosion Science and Technology

391 Pages·1998·2.658 MB·English

by  David E.J. Talbot, James D.R. Talbot

Library of Congress Cataloging-in-Publication Data
Talbot, David
Corrosion science and technology/David Talbot and James Talbot
p. cm. (CRC series in materials science and technology)
Includes bibliographical references and index.
ISBN 0-8493-8224-6
1. Chemical engineering—materials science. 2. Mechanical engineering—materials
science. 1. Talbot, James. II. Title. III. Series
H749.H34B78 1997
616′.0149—dc20 97-57109
CIP
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International Standard Book Number 0-8493-8224-6
Library of Congress Card Number 97-57109
Printed in the United States of America 2 3 4 5 6 7 8 9 0
Printed on acid-free paper
Contents
Preface
1 Overview of Corrosion and Protection Strategies
1.1 Corrosion in Aqueous Media
1.1.1 Corrosion as a System Characteristic
1.1.2 The Electrochemical Origin
of Corrosion
1.1.3 Stimulated Local Corrosion
1.2 Thermal Oxidation
1.2.1 Protective Oxides
1.2.2 Non-Protective Oxides
1.3 Environmentally Sensitive Cracking
1.4 Strategies for Corrosion Control
1.4.1 Passivity
1.4.2 Conditions in the Environment
1.4.3 Cathodic Protection
1.4.4 Protective Coatings
1.4.5 Corrosion Costs
1.4.6 Criteria for Corrosion Failure
1.4.7 Material Selection
1.4.8 Geometric Factors
1.5 Some Symbols, Conventions, and Equations
1.5.1 Ions and Ionic Equations
1.5.2 Partial Reactions
1.5.3 Representation of Corrosion Processes
2 Structures Concerned in Corrosion Processes
2.1 Origins and Characteristics of Structure
2.1.1 Phases
2.1.2 The Role of Electrons in Bonding
2.1.3 The Concept of Activity
2.2 The Structure of Water and Aqueous Solutions
2.2.1 The Nature of Water
2.2.2 The Water Molecule
2.2.3 Liquid Water
2.2.4 Autodissociation and pH of Aqueous
Solutions
2.2.5 The pH Scale
2.2.6 Foreign Ions in Solution
2.2.7 Ion Mobility
2.2.8 Structure of Water and Ionic Solutions
at Metal Surfaces
2.2.9 Constitutions of Hard and Soft
Natural Waters
2.3 The Structures of Metal Oxides
2.3.1 Electronegativity
2.3.2 Partial Ionic Character of Metal Oxides
2.3.3 Oxide Crystal Structures
2.3.4 Conduction and Valence Electron
Energy Bands
2.3.5 The Origins of Lattice Defects
in Metal Oxides
2.3.6 Classification of Oxides by Defect Type
2.4 The Structures of Metals
2.4.1 The Metallic Bond
2.4.2 Crystal Structures and Lattice Defects
2.4.3 Phase Equilibria
2.4.4 Structural Artifacts Introduced
During Manufacture
3 Thermodynamics and Kinetics of Corrosion Processes
3.1 Thermodynamics of Aqueous Corrosion
3.1.1 Oxidation and Reduction Processes
in Aqueous Solution
3.1.2 Equilibria at Electrodes and the
Nernst Equation
3.1.3 Standard State for Activities of Ions
in Solution
3.1.4 Electrode Potentials
3.1.5 Pourbaix (Potential-pH) Diagrams
3.2 Kinetics of Aqueous Corrosion
3.2.1 Kinetic View of Equilibrium at an Electrode
3.2.2. Polarization
3.2.3 Polarization Characteristics
and Corrosion Velocities
3.2.4 Passivity
3.2.5 Breakdown of Passivity
3.2.6 Corrosion Inhibitors
3.3 Thermodynamics and Kinetics of Dry Oxidation
3.3.1 Factors Promoting the Formation
of Protective Oxides
3.3.2 Thin Films and the Cabrera-Mott Theory
3.3.3 Thick Films, Thermal Activation
and the Wagner Theory
3.3.4 Selective Oxidation of Components
in an Alloy
Sample Problems and Solutions
Appendix: Construction of Some Pourbaix Diagrams
4 Mixed Metal Systems and Cathodic Protection
4.1 Galvanic Stimulation
4.1.1 Bimetallic Couples
4.1.2 The Origin of the Bimetallic Effect
4.1.3 Design Implications
4.2 Protection by Sacrificial Anodes
4.2.1 Principle
4.2.2 Application
4.3 Cathodic Protection by Impressed Current
5 The Intervention of Stress
5.1 Stress-Corrosion Cracking (SCC)
5.1.1 Characteristic Features
5.1.2 Stress-Corrosion Cracking in Aluminum
Alloys
5.1.3 Stress-Corrosion Cracking in Stainless
Steels
5.1.4 Stress-Corrosion Cracking in Plain
Carbon Steels
5.2 Corrosion Fatigue
5.2.1 Characteristic Features
5.2.2 Mechanisms
5.3 Erosion-Corrosion and Cavitation
5.3.1 Erosion-Corrosion
5.3.2 Cavitation
5.4 Precautions Against Stress-Induced Failures
6 Protective Coatings
6.1 Surface Preparation
6.1.1 Surface Conditions of Manufactured
Metal Forms
6.1.2 Cleaning and Preparation of Metal
Surfaces
6.2 Electrodeposition
6.2.1 Application and Principles
6.2.2 Electrodeposition of Nickel
6.2.3 Electrodeposition of Copper
6.2.4 Electrodeposition of Chromium
6.2.5 Electrodeposition of Tin
6.2.6 Electrodeposition of Zinc
6.3 Hot-Dip Coatings
6.3.1 Zinc Coatings (Galvanizing)
6.3.2 Tin coatings
6.3.3 Aluminum Coatings
6.4 Conversion Coatings
6.4.1 Phosphating
6.4.2 Anodizing
6.4.3 Chromating
6.5 Paint Coatings for Metals
6.5.1 Paint Components
6.5.2 Application
6.5.3 Paint Formulation
6.5.4 Protection of Metals by Paint Systems
7 Corrosion of Iron and Steels
7.1 Microstructures of Irons and Steels
7.1.1 Solid Solutions in Iron
7.1.2 The Iron-Carbon System
7.1.3 Plain Carbon Steels
7.1.4 Cast Irons
7.2 Rusting
7.2.1 Species in the Iron-Oxygen-Water System
7.2.2 Rusting in Aerated Water
7.2.3 Rusting in Air
7.2.4 Rusting of Cast Irons
7.3 The Oxidation of Iron and Steels
7.3.1 Oxide Types and Structures
7.3.2 Phase Equilibria in the Iron–Oxygen
System
7.3.3 Oxidation Characteristics
7.3.4 Oxidation of Steels
7.3.5 Oxidation and Growth of Cast Irons
8 Stainless Steels
8.1 Phase Equilibria
8.1.1 The Iron-Chromium System
8.1.2 Effects of Other Elements on the
Iron-Chromium System
8.1.3 Schaeffler Diagrams
8.2 Commercial Stainless Steels
8.2.1 Classification
8.2.2 Structures
8.3 Resistance to Aqueous Corrosion
8.3.1 Evaluation from Polarization
Characteristics
8.3.2 Corrosion Characteristics
8.4 Resistance to Dry Oxidation
8.5 Applications
8.5.1 Ferritic Steels
8.5.2 Austenitic Steels
8.5.3 Hardenable Steels
8.5.4 Duplex Steels
8.5.5 Oxidation-Resistant Steels
Problems and Solutions
9 Corrosion Resistance of Aluminum and Its Alloys
9.1 Summary of Physical Metallurgy of Some
Standard Alloys
9.1.1 Alloys Used Without Heat Treatment
9.1.2 Heat Treatable (Aging) Alloys
9.1.3 Casting Alloys
9.2 Corrosion Resistance
9.2.1 The Aluminum-Oxygen-Water System
9.2.2 Corrosion Resistance of Pure Aluminum
in Aqueous Media
9.2.3 Corrosion Resistance of Aluminum Alloys
in Aqueous Media
9.2.4 Corrosion Resistance of Aluminum
and its Alloys in Air
9.2.5 Geometric Effects
10 Corrosion and Corrosion Control in Aviation
10.1 Airframes
10.1.1 Materials of Construction
10.1.2 Protective Coatings
10.1.3 Corrosion of Aluminum Alloys
in Airframes
10.1.4 External Corrosion
10.1.5 Systematic Assessment for Corrosion
Control
10.1.6 Environmentally Sensitive Cracking
10.2 Gas Turbine Engines
10.2.1 Engine Operation
10.2.2 Brief Review of Nickel Superalloys
10.2.3 Corrosion Resistance
10.2.4 Engine Environment
10.2.5 Materials
10.2.6 Monitoring and Technical
Development
11 Corrosion Control in Automobile Manufacture
11.1 Overview