MECHANOCHEMISTRY OF MATERIALS

E M Gutman

Professor oj Materials Engineering, Ben-Gurion University oj the Negev, Israel

CAMBRIDGE INTERNATIONAL SCIENCE PUBLISHING

CONTENTS

PREFACE INTRODUCTION

1 MAIN SPECIAL FEATURES OF THE BEHAVIOUR OF SOLIDS WTTH REFERENCE TO MECHANOCHEMISTRY 1

1.1 Solid State thermodynamics 1 1.1.1 First law of thermodynamics 1 1.1.2 Enthalpy 2 1.1.3 The second law of thermodynamics and free energy 5 1.1.4 Statistical interpretation of entropy 8 1.1.5 Third law of thermodynamics 9 1.1.6 Relationships for free Gibbs energy 9 1.1.7 Chemical equilibrium 11 1.1.8 Partial molar thermodynamic functions 15 1.1.9 Chemical potential 19 1.2 Deformation and hardening of crystalline and amorphous materials 23 1.2.1 Elastic deformation 23 1.2.2 Plastic deformation of a crystalline solid 27 1.2.3 Viscoelastic properties of amorphous materials 32 1.3 Surface phenomena 36

2 NON-EQUILIBRIUM THERMODYNAMICS AND KINETICS OF MECHANOCHEMICAL PHENOMENA 39 2.1 Main assumption of the thermodynamics of irreversible processes 39 2.2 Chemical kinetics and entropy production 44 2.2.1 Chemical kinetics 44 2.2.2 Entropy production in a chemical reaction 49 2.3 Heterogeneous equilibria and reactions 52 2.3.1 Surface tension in solids 52 2.3.2 Effect of surface on heterogeneous equilibria 60 2.3.3 Effect of pressure on the kinetics of chemical reactions in classic

representation 62 2.4 Mechanochemical activity of the substance and reaction kinetics 64 2.4.1 General definition of mechanochemical activity 64 2.4.2 Mechanochemical activity and kinetics of reactions in hydrostatic

compression and expansion of solids 68 2.4.3 Contribution of the energy of structural defects of the solid to the

mechanochemical activity and kinetics 73 2.4.3.1 Dislocations 73 2.4.3.2 Point defects 82

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3 IRREVERSIBLE INTERACTTONS OF PROCESSES OF CHEMICAL REACTION, PLASTIC DEFORMATION AND DISPERSION OF THE SOLD3 86 3.1 Entropy production 86 3.1.1 Chemical potential of dislocations 86 3.1.2 Entropy production in plastic deformation 90 3.1.3 Entropy production in dispersion process 92 3.2 Phenomenological kinetic equations 94 3.3 Chemomechanical effect 96 3.3.1 Quantitative analysis 96 3.3.2 Experiments 98

4 KINETICS OF MECHANOCHEMICAL REACTIONS UNDER WELL-DEFINED STRESS CONDITIONS 103 4.1 Loading below yield stress 103 4.1.1 Metals 103 4.1.2 Minerals 107 4.1.3 Polymers 111 4.2 Plastic deformation 112 4.2.1 Kinetic equation 112 4.2.2 Mechanoelectrochemical reactions 118 4.2.3 Inhibition of the mechanoelectrochemical effect 123 4.2.4 Mechanoemission of electron 125 4.2.4.1 Internal double layer 125 4.2.4.2 Mechanoinduced electron emission 131 4.2.5 Surface modification 134 4.2.5.1 Mechanical treatment 134 4.2.5.2 Mechanochemical treatment 139 4.2.5.3 Plasticizing by etching 142 4.2.6 Microelectrochemical heterogeneity 144 4.2.7 Corrosion fatigue 147 4.2.8 Relaxation failure of polymers and composites 152

5 KINETICS OF MECHANOCHEMICAL REACTIONS UNDER NON-DEFINED STRESS CONDITIONS 162 5.1 Mechanical excitation caused by failure of materials 162 5.2 Refining and comminution 164 5.3 Some phenomena accompanying dispersion of solids 168 5.4 Mechanoactivation of minerals 170 5.5 Mechanopolymerization 172 5.6 Ultrasound and shock waves 176

6 SOME APPLICATIONS OF MECHANOCHEMISTRY IN MATERIALS TECHNOLOGY 178 6.1 Advantages of using mechanochemistry in materials technology 178 6.2 Using mechanochemical phenomena in metallurgy and technology of

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inorganic matenals 183 6.3 Production of composites 189 6.4 Production of structural materials 192 6.5 Mechanical alloying and nanoscaled materials 195 Recommended books and monographs on mechanochemistry 200 List of Symbols 201 Index 209

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