Phase Transformations in Metals and Alloys

Phase Transformations in Metals and Alloys

(Parte 1 de 15)

Published by Chapan L Hall, 2-6 Bormdary Row, London SEl m, LX

Chapman & Hall, 2-6 Boundary Raw, London SEl 8HN, UK Chapman & Eldl GmbH, Pappclallee 3, 69469 Wtinbeim, Germany

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First edition 1981

Reprinted 1982, 1983, 1984, 1986, 1987, 1988, 1989, 1990, 1992 Second edition 1992 Reprinted I993 (twice), 1995, 1996

0 1981, I992 D.A. Porter and K.E. Easterling

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Preface to the second edition Preface to rhe first edition

I Thermodynamia and Phase Diagrams 1.1 Equilibrium 1.2 Single ~orn~o'nenf Systems 1.3.1 Gibhs Free Energy as a Function of Temperature 1.1.1 Pressure Effects

1.2.3 The Driving Force for Soliditicatiun 1.3 Binary Solutions 1.3.1 The Gibbs Free Enerpy of Binary Solutions 1.3.2 Ideal Solutions

1.3.3 Chemical Potential 1.3.4 Regular Solutions 1.3.5 Activity 1.3.6 Real Solutions

1.3.7 Ordered Phases 1.3.8 Intermediate Phases 1.3 Equilibrium in Heterogeneous Systems

1.5 Binary Phase Diagrams

I 3.1 A Simple Phase Diagram 1.5.2 Systems with a Miscibility Gap 1.5.3 Ordered Alloys 1.5.4 Simple Eutectic Systems 1.5.5 Phase Diagrams Containing Intermediate Phases

1.5.6 TheGibbsPhaseRule 1.5.7 The Effect of Temperature on Solid Solubility

1.5.1: Equilibrium Vacancy Concentration 1.6 The Influence of Interfaces on Equilibrium 1.7 Ternary Equilibrium

1.8 Additional Thermodynamic Relationships for Binary Solutions 1.9 The Kinetics of Phase Transformations

References Further Reading Exercises xi xii vi Con (en IS

2 Diffusion 2.1 Atomic Mechanisms of Diffusion 2.2 Interstitial Diffusion

2.7.1 Interstitial Diffusion as a Random Jump Process 2.2.2 Effect of Temperature-Thermal Activation 2.2.3 Steady-State Diffusion 2.2.4 Nonsteady-State Diffusion

2.2.5 Solutions to the Diffusion Equation


The Carburization of Steel 2.3 Substitutional Diffusion

2.3.1 Self-Diffusion 2.3.2 Vacancy Diffusion

2.3.3 Diffusion in Substitutional Allnys

2.3.4 Diffusion in Dilute Substitutional Alloys 2.4 Atomic Mobility

2.5 Tracer Diffusion in Binary Alloys 2.6 Diffusion in Ternary Alloys 2.7 High-Diffusivity Paths

2.7.1 Diffusion along Grain Boundaries end Free Surfaces 2.7.2 Diffusion along Dislocations

2.8 Diffusion in Multiphase Binary Svstems


Further Reading Exercises

3 Crystal Interfaces and Microstructure 3.1 Interfacial Free Energy 3.2 SolidJVapour Interfaces 3.3 Boundaries in Single-Phase Solids 3.3.1 Low-Angle and High-Angle Boundaries 3.3.2 Special High-Angle Grain Boundaries 3.3.3 Equilibrium in Polycrystalline Materials

3.3.4 Thermally Activated Migration of Grain Boundaries

3.3.5 The Kinetics of Grain Growth 3.4 Interphase Interfaces in Solids

3.3. f Interface Coherence

Fully Coherent Interfaces Semicoheren t interfaces Incoherent Interfaces Complex Semicoherent Interfaces

3.4.2 Second-Phase Shape: Interfacial Energy Effects Fully Coherent Precipitates

Partially Coherent Precipitates

Incoherent Precipitates Precipitates on Grain Boundaries

Confen~s vii

(Parte 1 de 15)