Contents
Preface to the Japanese Edition……………………………………………………….ix
Preface to the English Edition……………………………………………………xi
Authors……………………………………………………………………………. xiii
Chapter 1 Introduction………………………………………………………….1
1.1 Interfacial Physical Chemistry……………………………………………1
1.2 Interface-Evolved World…………………………………………………….1
1.3 Relation to Engineering……………………………………………………..2
References…………………………………………………………………………………3
Chapter 2 Fundamentals of Treating the Interface……………………..5
2.1 Interface…………………………………………………………………………..5
2.2 Thermodynamic Treatment of the Interface…………………………5
2.2.1 Gibbs’ Method………………………………………………………5
2.2.2 Surface Tension…………………………………………………….7
2.2.2.1 Thermodynamic Interpretation of
Surface Tension……………………………………….7
2.2.2.2 Surface Tension and the Position of the
Dividing Surface…………………………………… 10
2.2.2.3 Surface Tension and Radius of Curvature… 11
2.2.2.4 Surface Tension and Binding Energy………. 14
2.2.2.5 Surface Tension and Temperature…………… 15
2.2.2.6 Surface Tension and Surface Stress…………. 16
2.3 Mechanical Treatment of Interface…………………………………… 18
2.3.1 Mechanical Interpretation of Surface Tension………… 18
2.3.2 Laplace’s Equation………………………………………………20
2.3.3 Marangoni Effect………………………………………………..22
2.4 Interfacial Phenomena at Equilibrium……………………………….25
2.4.1 Adsorption………………………………………………………….25
2.4.1.1 Gibbs’ Adsorption Equation……………………25
2.4.2 Wetting………………………………………………………………28
2.4.2.1 Classification of Wetting…………………………28
2.4.2.2 Measure of Wetting……………………………….29
2.4.2.3 Extension of the Wetting Concept…………… 31
2.4.3 Effect of Curvature……………………………………………… 32
2.4.3.1 Vapor Pressure……………………………………… 32
2.4.3.2 Heat of Vaporization………………………………34
2.4.3.3 Melting Point………………………………………..36
2.4.3.4 Solubility……………………………………………… 37
2.4.3.5 Phase Rule…………………………………………… 39
2.4.4 Nucleation………………………………………………………….. 41
2.4.4.1 Homogeneous Nucleation………………………. 41
2.4.4.2 Heterogeneous Nucleation……………………… 45
2.5 Interfacial Properties and Phenomena at Non-Equilibrium…..46
2.5.1 Interfacial Properties……………………………………………46
2.5.1.1 Surface Tension…………………………………….. 47
2.5.1.2 Interfacial Tension…………………………………48
2.5.1.3 Wettability (Contact Angle)…………………….49
2.5.2 Interfacial Phenomenon………………………………………. 51
2.5.2.1 Nucleation Rate…………………………………….. 51
2.5.2.2 Marangoni Effect………………………………….. 52
2.5.2.3 Dispersion……………………………………………. 53
2.5.2.4 Penetration…………………………………………… 57
References………………………………………………………………………………. 58
Chapter 3 Interfacial Property of High-Temperature Melts………………………….. 61
3.1 Notes on Measurement Values…………………………………………. 61
3.1.1 Measurement Error…………………………………………….. 61
3.1.2 Difficulties in Measurements……………………………….. 62
3.1.2.1 Surface Tension of Metal……………………….. 62
3.1.2.2 Surface Tension of Slag………………………….63
3.1.2.3 Interfacial Tension between Slag and
Metal……………………………………………………64
3.1.2.4 Wettability (Contact Angle)…………………….65
3.2 Surface–Interfacial Tension……………………………………………..66
3.2.1 Surface Tension of Metal……………………………………..66
3.2.2 Surface Tension of Slag………………………………………..69
3.2.3 Slag–Metal Interfacial Tension…………………………….. 71
3.3 Wettability between Metal and Ceramics………………………….. 72
3.3.1 Characteristics of Wetting between Molten
Metal and Oxide…………………………………………………. 72
3.3.2 Effect of the Chemical Composition of Metal
and Oxide………………………………………………………….. 73
3.3.3 Physical Form and Factor of Surface…………………….. 76
3.3.3.1 Surface Roughness……………………………….. 76
3.3.3.2 Structure of Interface…………………………….. 76
3.4 Databook and Review Paper……………………………………………..77
3.4.1 Databook…………………………………………………………… 79
3.4.2 Review………………………………………………………………. 79
References………………………………………………………………………………. 79
Chapter 4 Interfacial Phenomena of High-Temperature Melts and
Materials Processing………………………………………………………………… 81
4.1 Interfacial Phenomena in the Steel Refining Process……………82
4.1.1 Wetting………………………………………………………………82
4.1.1.1 Behavior of Injected Argon Gas in a
Continuous Casting Process……………………82
4.1.1.2 Penetration of Slag and Metal into a
Refractory…………………………………………….83
4.1.2 Nucleation of Alumina in Aluminum
Deoxidation Processes in Molten Steel…………………..87
4.1.3 Others………………………………………………………………..87
4.1.3.1 Dispersion…………………………………………….87
4.1.3.2 Adsorption……………………………………………89
4.2 Marangoni Effect in Materials Processing………………………….90
4.2.1 Direct Observation of Marangoni Effect
Occurring in High-Temperature Melts……………………90
4.2.1.1 Marangoni Convection Due to the
Temperature Gradient…………………………….90
4.2.1.2 Expansion and Contraction of a Slag
Droplet Caused by Electric Potential
Change…………………………………………………93
4.2.1.3 Motion of Slag Film Caused by the
Concentration Gradient…………………………..95
4.2.2 Local Corrosion of Refractory………………………………96
4.2.2.1 Oxide Refractory…………………………………..96
4.2.2.2 Oxide–Non-Oxide Composite
Refractory………………………………………….. 101
4.2.3 Motion of Fine Particles in Liquid Under
Interfacial Tension Gradients……………………………… 103
4.2.3.1 Motion of Fine Bubbles in Aqueous
Solution under Surface Tension
Gradient…………………………………………….. 104
4.2.3.2 Engulfment and Pushing of Fine
Particles at the Solidification
Interface…………………………………………….. 107
4.2.3.3 Clogging of the Immersion Nozzle………… 109
References……………………………………………………………. 113
Index……………………………………………………………………… 117
Preface to the English Edition
This book was first published in 2007 by AGNE Gijutsu Center with the following title: Kouon-yuutai No Kaimen-butsurikagaku. This book is its English translation. For the last 10 years, I presented the research results described in this book at every opportunity, and it attracted many researchers. For example, the theory and experimental results from microgravity experiments on the movement of fine particles caused by the surface tension gradient attracted researchers involved in the nozzle clogging problem in the continuous casting process. The work on the mechanism of the local corrosion of refractories has a good reputation, and the in situ observation of the penetration behavior of molten slag and molten metal into porous refractories has also received much recognition.
Professor Kusuhiro Mukai—the author of this book and my supervisor when I was a Ph.D. student—asked me to write and publish a revised enlarged edition of the above-mentioned Japanese book in English. However, in May 2018, while we were preparing the English edition, Professor Mukai passed away, and I felt that it was not appropriate to revise the book without his supervision. Then, encouraged by the graduate students of Prof. Mukai’s lab, we collaborated to publish this English edition as a lasting tribute to his work. This book is basically translated from the Japanese edition, but some notes have been added by the translation supervisor.
Throughout the preparation, I have received the cooperation from the Japanese edition publisher, AGNE Gijutsu Center. Moreover, last but not least, I wish to acknowledge the contributions to the publication of this English edition by Prof. Mukai’s former students who graduated from the laboratory during his more than 30-year career at the Kyushu Institute of Technology.