Advances in Materials Research – serie

In this volume we aim to introduce recent progress in the study of aperiodic materials, which include icosahedral clusters, amorphous metals, quasicrys- tals, glasses, and liquids. Quasicrystals, discovered in 1984, correspond to a kind of revolution in our understanding of crystallography, wherein the five-fold rotational symmetry was prohibited in long-range ordered systems. Various interesting physicochemical properties of these materials strongly depend on structural inhomogeneity at the microscopic level, and the small angle X-ray scattering method is widely used to analyze such structures. These new materials provide fundamental improvements to materials prop- erties, and are not only scientifically interesting but also industrially impor- tant for applications such as ultrafine magnetic recording media and future electronic devices. This book contains three chapters. The first chapter, written by H. Tanaka and T. Fujiwara, deals with 'Electronic Structure in Aperiodic Materials', and reviews the application of theoretical methods to determine the elec- tronic structures and resulting properties of amorphous metals, quasicrys- tals, and liquids.The second chapter, written by Y. Waseda, K. Sugiyama, and A. H. Shinohara, covers the recent topic of 'Anomalous Small Angle X- ray Scattering for Structural Inhomogeneity of Materials', starting with its fundamentals. The third chapter, 'Icosahedral Clusters in RE(TM - Al h3 1 x x Amorphous Alloys', by K. Fukamichi, A. Fujita, T. H. Chang, E. Matsubara, and Y.

It is well known that corrosion products, i.e. rust, on iron and steel surfaces cannot be assigned a typical crystallographic structure with long-range order. In fact, the structure of rust is considered to be very complicated, and some forms of rust are assigned to the amorphous state for this reason. Accurate information about the atomic-scale structure of rust is important to shed light on corrosion mechanisms of metallic materials. And, since life of steel structures is often dominated by environmental degradation or corrosion of the surface, the structure of the rust formed on iron and steel surfaces during prolonged exposure to air is of great interest. This book describes the fundamental aspects of materials characterization for the ferric oxyhydroxides formed on steel surfaces. Selected examples, from both the basic science and the applied engineering points of view, are presented. Of special interest is the new structural information on ferric oxyhydroxides containing a small amount of alloying elements. The text relates this to their various states and their role in corrosion processes. This monograph will serve as a valuable guide and source of information for specialists and non-specialists alike.

Fiber Crystal Growth from the Melt reviews the growth, modelling, characterization and application of single crystal fibers are reviewed. Due to their very large length-to-diameter ratio together with perfect crystallographic structure and chemical homogeneity, such fibers have mechanical and physical properties that approach the theoretical values. Fukuda explains how their ultra-high strength enables their application as reinforcing agents in structural components. And he elucidates how and why fiber crystals are particularly well suited for wave guiding, tunable narrow-band filters and nonlinear optics and for the generation of green, blue and violet wavelenghts, and also as micro lasers and laser modulators. The book is suitable for specialists and students in the fields of materials science, crystal growth, physics, chemistry, crystallography, optics, mechanics and engineering.

There is no strict definition of the term "High Magnetic Field". It has been proposed to use this term for magnetic fields that are technically difficult to generate and therefore need special equipment or large resources. Static fields above 20 T are apparently high magnetic fields in this sense, but in the case of pulsed field 40 T is easy to obtain and any field lower than this approximate limit should not be considered as "high". When a static field is used for materials processing, even 10 T is considered as "high" because the long-term use of a conventional superconducting magnet is difficult. Recently, there has been much technical progress in producing high mag­ netic fields, both pulsed and static; in large part this is due to the devel­ opment of new materials. Complicated poly-helix coils are now replaced by simple Bitter coils made with plates of CuAg alloy with high strength and high conductivity; these are used in both water-cooled and hybrid magnets (now up to 45 Tat NHMFL, the US National High Magnetic Field Labora­ tory at Tallahassee, Florida). By using CuAg wire, a nondestructive pulsed field record of 80 T has been achieved at Osaka University. For daily use in experiments, 70-75 T should soon become available. Major facilities for static high fields worldwide are planning to generate fields over 40 T by increasing the electric power. On the other hand, the use of static high magnetic fields is expanding.

This book introduces a recent development in the theoretical research into the dynamic behaviour of fracture. This field is really a new trend in mechanical engineering and because of the interdisciplinary applications, physicists and materials scientists are also interested in the subject. The book has a review paper and about 20 high-level contributions. The main benefit to the reader is in showing how the recent development of molecular dynamics and other state-of-the-art methods can really solve the important problem of fracture from the atomic level.

This book covers several of the most important topics of current interest at the forefront of scanning probe microscopy. These include a realistic theory of atom-resolving atomic force microscopy (AFM), fundamentals of MBE growth of III-V compound semiconductors and atomic manipulation for future single-electron devices.

Amorphous and nanocrystalline materials are a class of their own. Their properties are quite different to those of the corresponding crystalline materials. This book gives systematic insight into their physical properties, structure, behaviour, and design for special advanced applications. The book will appeal to researchers, research engineers and advanced students in materials science.

This volume offers an overview of the growth of shaped crystals (oxides, fluorides, etc.) by the micro-pulling-down technique. Both melt and solution (flux) growth are considered. The advantages and disadvantages of the method are discussed in detail and compared with related crystal-growth processes. The authors attempt to give a practical introduction to this technique, thereby also explaining how its application can help to solve problems commonly encountered in other melt-growth methods.

In nanotechnology to date, much emphasis is placed on the creation of the nanostructures by means of micro- and atomic manipulations. This research ?eld has been highly respected and promoted by the society, polytics, and economics. Rapid progress in this ?eld has been greatly stimulated by more fundamental study on nano- and micromaterials. In this respect, the sci- tists and engineers in di?erent ?elds of physics, chemistry, materials science, and information technology including experimentalists, theorists, and also researchers doing computer simulations have collaborated to form a new interdisciplinary ?eld. This book covers the recent advances in this growing research ?eld, in particular, those developed mainly in the interdisciplinary research project named “Materials science for nano- and microscale control: Creation of new structures and functions,” which was formed in 2004 in the Graduate School of Engineering of Yokohama National University in collaboration with the Institutefor Materials Research, Tohoku University and other universities. The topics described in this book are as follows.

New advanced materials are being rapidly developed, thanks to the progress of science. These are making our daily life more convenient. The Institute for Materials Research (IMR) at Tohoku University has greatly contributed for to the creation and development of various advanced materials and the progress in the ?eld of material science for almost a century. For example, our early research achievements on the physical metallurgy of iron carbon alloys led to the innovation of technology for making high-quality steels, which has greatly contributed to the advancement of the steel and related industry in Japan and rest of the world. IMR has focused on basic research that can be translated into applications in the future, for the bene?t of mankind. With this tradition, we have established the ?rst high-magnetic ?eld as well as low-temperature technologies in Japan, which were essential to the - vancement of magnetism and superconductivity. Recently, IMR has expanded its research in the ?eld of advanced materials including metallic glasses, - ramics, nano-structural metals, semiconductors, solar cell crystals, new op- andspin-electronicsmaterials,organicmaterials,hydrogenstoragealloys,and shaped crystals. Inthefaceofthecrisisofthedestructionoftheglobalenvironment,the- pletion of world-wide natural resources, and the exhaustion of energy sources in the twenty-?rst century, we all have an acute/serious desire for a b- ter/safer world in the future. IMR has been and will continue the pursuit of research aimed at solving global problems and furthering eco-friendly dev- opment.

A variety of industries – information technology, aerospace, automobile, and basic and new materials manufacturing – need technological innovations, which bring high-value-added and high-quality products at low cost not only because of global competition, but also because of the perspective of en- ronmental consciousness and regulation. Thermophysical properties of hi- temperature melts are indispensable for numerical simulations of material processes such as semiconductor and optical crystal growth of the melt, and castingofsuper-high-temperaturealloysforjet-engineturbineblades,inad- tion to welding in automobile manufacturing. Recent developments in process modeling provide 3D unsteady analysis of melt convection, temperature, and heat ?ux distribution, which enables us to predict product quality. In fact, 3D process visualization using computer modeling helps us to understand complicated phenomena occurring in the melt and to control the process. Accurate data are necessary to improve the modeling, which co- e?ectively engenders high-quality products. However, crucial obstacles render measurements of thermophysical properties di?cult at elevated temperatures because of high chemical reactivity and ?uidity of melts. Substantial and persistent challenges have been made to ascertain the precise thermophysical properties of high-temperature melts. This book describes the new techniques and latest developments in the measurements of atomic structure, density, surface tension, viscosity, heat capacity, thermal and mass di?usivity, th- mal conductivity, emissivity, and electrical conductivity of high-temperature melts. In addition to up-to-date improvements in conventional techniques, some new attempts are introduced to open a new scienti?c ?eld, that is,physics of high-temperature melts.

Semiconducting oxides and nitrides are becoming the most important s- jects in materials science. In particular, zinc oxide (ZnO), gallium nitride (GaN), and related compounds form a novel class of semiconductors which possess unique properties in terms of crystallography, crystal growth, op- cal properties, electrical properties, magnetic properties, and so forth. These uniquepropertiesmakethesematerialsquiteimportantinoptoelectronicsand electronics. Although for more than three decades oxide and nitride semiconductors have been known to possess unique properties, it is only recently that these materials have been exploited to fabricate novel electronic and optical - vices, which havenever been possible with other semiconductors. It should be mentioned that revolutionary breakthroughs in materials science have been madebeforethe remarkabledevelopmentofsuchdevices.In particular,recent breakthrough and advance in epitaxy, bulk growth, and synthesis of nan- tructures coupled with exploration and investigation on structural, optical, and electrical properties, enabled us to achieve novel display, general lig- ing, optical storage, high-speed, -temperature and -power electronics, bio and environmental sensors, and energy generating and saving devices.The unique structure of this book is that each chapter addresses both oxides and nitrides, which, we believe, will help readers gain comprehensive and comparative information on oxide and nitride semiconductors. This book consists of ten chapters, addressing the basic properties of materials, bulk growth,?lm growth,polarityissues, nonpolar?lms, structuraldefects, optical properties, electrical properties, light emitting diodes, and nanostructures. Thus the book covers processing, properties, and applications of materials based on ZnO, GaN, and related compounds.

Synthesis and application of nanoparticles have been often reported by researchers in material science, chemistry and physics. While nanoparticles themselves are well known to exhibit fascinating characteristics. interest in their improvement and promotion is now turning to the hybridization of organic and/or inorganic nano-materials. Although nano-level hybridization is an outstandingly novel and original technique, it encounters many difficulties to achieving the desired industrial application. To thoroughly review the research in this field, this book focuses on the synthesis, characterization and process of nano-hybrid materials, including nanoparticles and ultra-thin films.It elucidates the fundamental aspects of nano-hybrid materials in the synthesis procedure, characterization, and processes with selected examples, from both the basic science and the engineering appications points of view. In fact, this is the first comprehensive compilation of new advances that covers the current status and topics of new synthetic information of nano-hybrid materials composed of organic and/or inorganic materials at the nano-meter level, in one volume. As such, the book provides a unique source of information and guidance for specialists and non-specialists alike.

This book, a continuation of the series “Advances in Materials Research,” is intended to provide the general basis of the science and technology of crystal growth of silicon for solar cells. In the face of the destruction of the global environment,the degradationofworld-widenaturalresourcesandtheexha- tion of energy sources in the twenty-?rst century, we all have a sincere desire for a better/safer world in the future. In these days, we strongly believe that it is important for us to rapidly developanewenvironment-friendlycleanenergyconversionsystemusingsolar energyastheultimatenaturalenergysource. Forinstance,mostofournatural resources and energy sources will be exhausted within the next 100 years. Speci?cally, the consumption of oil, natural gas, and uranium is a serious problem. Solar energy is the only ultimate natural energy source. Although 30% of total solar energy is re?ected at the earth’s surface, 70% of total solar energy can be available for us to utilize. The available solar energy amounts to severalthousand times larger than the world’s energy consumption in 2000 of about 9,000 Mtoe (M ton oil equivalent). To manage 10% of the world’s energy consumption at 2050 by solar energy, we must manufacture 40 GW solar cells per year continuously for 40 years. The required silicon feedstock is about 400,000 ton per year. We believe that this is an attainable target, since it can be realized by increasing the world production of silicon feedstock by 12times asmuchasthe presentproductionat2005.

In this volume we aim to introduce recent progress in the study of aperiodic materials, which include icosahedral clusters, amorphous metals, quasicrys- tals, glasses, and liquids. Quasicrystals, discovered in 1984, correspond to a kind of revolution in our understanding of crystallography, wherein the five-fold rotational symmetry was prohibited in long-range ordered systems. Various interesting physicochemical properties of these materials strongly depend on structural inhomogeneity at the microscopic level, and the small angle X-ray scattering method is widely used to analyze such structures. These new materials provide fundamental improvements to materials prop- erties, and are not only scientifically interesting but also industrially impor- tant for applications such as ultrafine magnetic recording media and future electronic devices. This book contains three chapters. The first chapter, written by H. Tanaka and T. Fujiwara, deals with 'Electronic Structure in Aperiodic Materials', and reviews the application of theoretical methods to determine the elec- tronic structures and resulting properties of amorphous metals, quasicrys- tals, and liquids.The second chapter, written by Y. Waseda, K. Sugiyama, and A. H. Shinohara, covers the recent topic of 'Anomalous Small Angle X- ray Scattering for Structural Inhomogeneity of Materials', starting with its fundamentals. The third chapter, 'Icosahedral Clusters in RE(TM - Al h3 1 x x Amorphous Alloys', by K. Fukamichi, A. Fujita, T. H. Chang, E. Matsubara, and Y.

Fiber Crystal Growth from the Melt reviews the growth, modelling, characterization and application of single crystal fibers are reviewed. Due to their very large length-to-diameter ratio together with perfect crystallographic structure and chemical homogeneity, such fibers have mechanical and physical properties that approach the theoretical values. Fukuda explains how their ultra-high strength enables their application as reinforcing agents in structural components. And he elucidates how and why fiber crystals are particularly well suited for wave guiding, tunable narrow-band filters and nonlinear optics and for the generation of green, blue and violet wavelenghts, and also as micro lasers and laser modulators. The book is suitable for specialists and students in the fields of materials science, crystal growth, physics, chemistry, crystallography, optics, mechanics and engineering.

This book introduces a recent development in the theoretical research into the dynamic behaviour of fracture. This field is really a new trend in mechanical engineering and because of the interdisciplinary applications, physicists and materials scientists are also interested in the subject. The book has a review paper and about 20 high-level contributions. The main benefit to the reader is in showing how the recent development of molecular dynamics and other state-of-the-art methods can really solve the important problem of fracture from the atomic level.

Amorphous and nanocrystalline materials are a class of their own. Their properties are quite different to those of the corresponding crystalline materials. This book gives systematic insight into their physical properties, structure, behaviour, and design for special advanced applications. The book will appeal to researchers, research engineers and advanced students in materials science.

This volume offers an overview of the growth of shaped crystals (oxides, fluorides, etc.) by the micro-pulling-down technique. Both melt and solution (flux) growth are considered. The advantages and disadvantages of the method are discussed in detail and compared with related crystal-growth processes. The authors attempt to give a practical introduction to this technique, thereby also explaining how its application can help to solve problems commonly encountered in other melt-growth methods.

In nanotechnology to date, much emphasis is placed on the creation of the nanostructures by means of micro- and atomic manipulations. This research ?eld has been highly respected and promoted by the society, polytics, and economics. Rapid progress in this ?eld has been greatly stimulated by more fundamental study on nano- and micromaterials. In this respect, the sci- tists and engineers in di?erent ?elds of physics, chemistry, materials science, and information technology including experimentalists, theorists, and also researchers doing computer simulations have collaborated to form a new interdisciplinary ?eld. This book covers the recent advances in this growing research ?eld, in particular, those developed mainly in the interdisciplinary research project named “Materials science for nano- and microscale control: Creation of new structures and functions,” which was formed in 2004 in the Graduate School of Engineering of Yokohama National University in collaboration with the Institutefor Materials Research, Tohoku University and other universities. The topics described in this book are as follows.

New advanced materials are being rapidly developed, thanks to the progress of science. These are making our daily life more convenient. The Institute for Materials Research (IMR) at Tohoku University has greatly contributed for to the creation and development of various advanced materials and the progress in the ?eld of material science for almost a century. For example, our early research achievements on the physical metallurgy of iron carbon alloys led to the innovation of technology for making high-quality steels, which has greatly contributed to the advancement of the steel and related industry in Japan and rest of the world. IMR has focused on basic research that can be translated into applications in the future, for the bene?t of mankind. With this tradition, we have established the ?rst high-magnetic ?eld as well as low-temperature technologies in Japan, which were essential to the - vancement of magnetism and superconductivity. Recently, IMR has expanded its research in the ?eld of advanced materials including metallic glasses, - ramics, nano-structural metals, semiconductors, solar cell crystals, new op- andspin-electronicsmaterials,organicmaterials,hydrogenstoragealloys,and shaped crystals. Inthefaceofthecrisisofthedestructionoftheglobalenvironment,the- pletion of world-wide natural resources, and the exhaustion of energy sources in the twenty-?rst century, we all have an acute/serious desire for a b- ter/safer world in the future. IMR has been and will continue the pursuit of research aimed at solving global problems and furthering eco-friendly dev- opment.

A variety of industries – information technology, aerospace, automobile, and basic and new materials manufacturing – need technological innovations, which bring high-value-added and high-quality products at low cost not only because of global competition, but also because of the perspective of en- ronmental consciousness and regulation. Thermophysical properties of hi- temperature melts are indispensable for numerical simulations of material processes such as semiconductor and optical crystal growth of the melt, and castingofsuper-high-temperaturealloysforjet-engineturbineblades,inad- tion to welding in automobile manufacturing. Recent developments in process modeling provide 3D unsteady analysis of melt convection, temperature, and heat ?ux distribution, which enables us to predict product quality. In fact, 3D process visualization using computer modeling helps us to understand complicated phenomena occurring in the melt and to control the process. Accurate data are necessary to improve the modeling, which co- e?ectively engenders high-quality products. However, crucial obstacles render measurements of thermophysical properties di?cult at elevated temperatures because of high chemical reactivity and ?uidity of melts. Substantial and persistent challenges have been made to ascertain the precise thermophysical properties of high-temperature melts. This book describes the new techniques and latest developments in the measurements of atomic structure, density, surface tension, viscosity, heat capacity, thermal and mass di?usivity, th- mal conductivity, emissivity, and electrical conductivity of high-temperature melts. In addition to up-to-date improvements in conventional techniques, some new attempts are introduced to open a new scienti?c ?eld, that is,physics of high-temperature melts.

Semiconducting oxides and nitrides are becoming the most important s- jects in materials science. In particular, zinc oxide (ZnO), gallium nitride (GaN), and related compounds form a novel class of semiconductors which possess unique properties in terms of crystallography, crystal growth, op- cal properties, electrical properties, magnetic properties, and so forth. These uniquepropertiesmakethesematerialsquiteimportantinoptoelectronicsand electronics. Although for more than three decades oxide and nitride semiconductors have been known to possess unique properties, it is only recently that these materials have been exploited to fabricate novel electronic and optical - vices, which havenever been possible with other semiconductors. It should be mentioned that revolutionary breakthroughs in materials science have been madebeforethe remarkabledevelopmentofsuchdevices.In particular,recent breakthrough and advance in epitaxy, bulk growth, and synthesis of nan- tructures coupled with exploration and investigation on structural, optical, and electrical properties, enabled us to achieve novel display, general lig- ing, optical storage, high-speed, -temperature and -power electronics, bio and environmental sensors, and energy generating and saving devices.The unique structure of this book is that each chapter addresses both oxides and nitrides, which, we believe, will help readers gain comprehensive and comparative information on oxide and nitride semiconductors. This book consists of ten chapters, addressing the basic properties of materials, bulk growth,?lm growth,polarityissues, nonpolar?lms, structuraldefects, optical properties, electrical properties, light emitting diodes, and nanostructures. Thus the book covers processing, properties, and applications of materials based on ZnO, GaN, and related compounds.

This book, a continuation of the series “Advances in Materials Research,” is intended to provide the general basis of the science and technology of crystal growth of silicon for solar cells. In the face of the destruction of the global environment,the degradationofworld-widenaturalresourcesandtheexha- tion of energy sources in the twenty-?rst century, we all have a sincere desire for a better/safer world in the future. In these days, we strongly believe that it is important for us to rapidly developanewenvironment-friendlycleanenergyconversionsystemusingsolar energyastheultimatenaturalenergysource. Forinstance,mostofournatural resources and energy sources will be exhausted within the next 100 years. Speci?cally, the consumption of oil, natural gas, and uranium is a serious problem. Solar energy is the only ultimate natural energy source. Although 30% of total solar energy is re?ected at the earth’s surface, 70% of total solar energy can be available for us to utilize. The available solar energy amounts to severalthousand times larger than the world’s energy consumption in 2000 of about 9,000 Mtoe (M ton oil equivalent). To manage 10% of the world’s energy consumption at 2050 by solar energy, we must manufacture 40 GW solar cells per year continuously for 40 years. The required silicon feedstock is about 400,000 ton per year. We believe that this is an attainable target, since it can be realized by increasing the world production of silicon feedstock by 12times asmuchasthe presentproductionat2005.

Synthesis and application of nanoparticles have been often reported by researchers in material science, chemistry and physics. While nanoparticles themselves are well known to exhibit fascinating characteristics. interest in their improvement and promotion is now turning to the hybridization of organic and/or inorganic nano-materials. Although nano-level hybridization is an outstandingly novel and original technique, it encounters many difficulties to achieving the desired industrial application. To thoroughly review the research in this field, this book focuses on the synthesis, characterization and process of nano-hybrid materials, including nanoparticles and ultra-thin films.It elucidates the fundamental aspects of nano-hybrid materials in the synthesis procedure, characterization, and processes with selected examples, from both the basic science and the engineering appications points of view. In fact, this is the first comprehensive compilation of new advances that covers the current status and topics of new synthetic information of nano-hybrid materials composed of organic and/or inorganic materials at the nano-meter level, in one volume. As such, the book provides a unique source of information and guidance for specialists and non-specialists alike.

It is well known that corrosion products, i.e. rust, on iron and steel surfaces cannot be assigned a typical crystallographic structure with long-range order. In fact, the structure of rust is considered to be very complicated, and some forms of rust are assigned to the amorphous state for this reason. Accurate information about the atomic-scale structure of rust is important to shed light on corrosion mechanisms of metallic materials. And, since life of steel structures is often dominated by environmental degradation or corrosion of the surface, the structure of the rust formed on iron and steel surfaces during prolonged exposure to air is of great interest. This book describes the fundamental aspects of materials characterization for the ferric oxyhydroxides formed on steel surfaces. Selected examples, from both the basic science and the applied engineering points of view, are presented. Of special interest is the new structural information on ferric oxyhydroxides containing a small amount of alloying elements. The text relates this to their various states and their role in corrosion processes. This monograph will serve as a valuable guide and source of information for specialists and non-specialists alike.

There is no strict definition of the term "High Magnetic Field". It has been proposed to use this term for magnetic fields that are technically difficult to generate and therefore need special equipment or large resources. Static fields above 20 T are apparently high magnetic fields in this sense, but in the case of pulsed field 40 T is easy to obtain and any field lower than this approximate limit should not be considered as "high". When a static field is used for materials processing, even 10 T is considered as "high" because the long-term use of a conventional superconducting magnet is difficult. Recently, there has been much technical progress in producing high mag­ netic fields, both pulsed and static; in large part this is due to the devel­ opment of new materials. Complicated poly-helix coils are now replaced by simple Bitter coils made with plates of CuAg alloy with high strength and high conductivity; these are used in both water-cooled and hybrid magnets (now up to 45 Tat NHMFL, the US National High Magnetic Field Labora­ tory at Tallahassee, Florida). By using CuAg wire, a nondestructive pulsed field record of 80 T has been achieved at Osaka University. For daily use in experiments, 70-75 T should soon become available. Major facilities for static high fields worldwide are planning to generate fields over 40 T by increasing the electric power. On the other hand, the use of static high magnetic fields is expanding.