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

Chapman &Hall USA, 115 fifth P:*ermt, NEW YO&, NY 10003, USA

Chaimao Bt HaU Japan, l7?-Japan, Kyowa Building, 3F, 2-2-1 Ruahwachu, Chiyoda-b, Tokyo 102, Japan

Chapman &Hall Australia, 1M Dodds Stnet, South Mtlboumc, Victoria 3205, Australia

Chapman & Hall India, R. Seshadri, 32 Stcond Main Road, CIT East, Madnrs 600 035, India

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

Typeset in 10112pt Times by Bed-set Typcseuw hd, Rong Kong Printed in Gnat Brimin by T.J.Pms (j'adstow) Ltd, Cornwall

ISBN 0 412 45030 5

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Contents

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

Homogenization

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

References

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)

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