Supermagnets, Hard Magnetic Materials


Book Description

The book you are now holding represents the final step in a long process for the editors and organizers of the Advanced Study Institute on hard magnetic materials. The editors interest in hard magnetic materials began in 1985 with an attempt to better understand the moments associated with the different iron sites in Nd Fe B. These 14 moments can be obtained from neutron diffraction studies, but we qUickly realized that iron-57 Mossbauer spectroscopy should lead to a better determination of these moments. However, it was also realized that the complex Mossbauer spectra obtained for these hard magnetic materials could not be easily understood without a broad knowledge of their various structural, electronic, and magnetic properties. Hence it seemed useful to the editors to bring together scientists and engineers to discuss, in a tutorial setting, the various properties of these and future hard magnetic materials. We believe the inclusion of engineers as well as scientists in these discussions was essential because the design of new magnetic materials depends very much upon the mode in which they are used in practical devices.




Rare-earth Iron Permanent Magnets


Book Description

Rare-earth iron permanent magnets combine the magnetization of iron or cobalt with the anisotropy of a light rare-earth in intermetallic compounds which exhibit nearly ideal hysteresis. The rare-earth iron magnets are indispensable components in a vast range of electronic and electromechanical devices. This book covers the principles of permanent magnetism, magnet processing, and applications in a series of interlocking chapters written by experts in each area. Based on the findings of the Concerted European Action on Magnets, it is a definitive account of the field, designed to be read by physicists, materials scientists, and electrical engineers.




Applications of Analytical Techniques to the Characterization of Materials


Book Description

Over the last several years, the field of materials science has witnessed an explosion of new, advanced materials. They encompass many uses and include superconductors, alloys, glasses, and catalysts. Not only are there quite a number of new enhies into these generic classes of materials, but the materials themselves represent a wide array of physical forms as well. Bulk materials, for example, are being synthesized and applica tions found for them, while still other materials are being synthesized as thin films for yet still more new (and in some cases, as yet unknown) applications. The field continues to expand with (thankfully!) no end in sight as to the number of new possibilities. As work progresses in this area, there is an ever increasing demand for knowing not only what material is formed as an end product but also details of the route by which it is made. The knowledge of reaction mechanisms in their synthesis many times allows a researcher to tailor a preparative scheme to either arrive at the final product in a purer state or with a better yield. Also, a good fundamental experimental knowledge of impuri ties present in the final material helps the investigator get more insight into making it.




Micromagnetism and the Microstructure of Ferromagnetic Solids


Book Description

The main theme of this book is micromagnetism and microstructure as well as the analysis of the relations between characteristic properties of the hysteresis loop and microstructure. Also presented is an analysis of the role of microstructure in the fundamental magnetic properties (for example, magnetorestriction or critical behaviour) of crystalline and amorphous alloys. The authors apply the theory of micromagnetism to all aspects of advanced magnetic materials including domain patterns and magnetization processes under the influence of defect structures. Coverage includes modern developments in computational micromagnetism and its application to spin structures of small particles and platelets. It will be of interest to researchers and graduate students in condensed matter, physics, electrical engineering and materials science, as well as to industrial researchers working in the electrotechnical and recording industry.




Hexaferrite Permanent Magnetic Materials


Book Description

This concise book presents the basic concepts of magnetism and magnetic properties pertinent to permanent magnetic materials. Emphasis is placed on hexaferrite materials for permanent magnet applications, with M-type ferrites as the focal point. The relatively high metallicity of magnetic materials for practical applications imposes limitations for their efficient use. Accordingly, magnetic oxides with ferromagnetic properties emerged as the most widely used magnetic materials for practical applications, owing to their characteristic high resistivity and low eddy current losses, chemical stability, simplicity of production in mass quantities, and other favorable characteristics. An important class of these oxides is the class of hexagonal ferrites developed in the early 1950’s, which dominated the world market of permanent magnet applications since the end of the 1980’s. Among these ferrites, the magnetoplumbite (M-type) hexaferrite, is produced nowadays in large quantities at very competitive low prices, thus providing the permanent magnet market with probably the most cost-effective magnetic material.




Physics of Magnetism and Magnetic Materials


Book Description

In this book, the fundamentals of magnetism are treated, starting at an introductory level. The origin of magnetic moments, the response to an applied magnetic field, and the various interactions giving rise to different types of magnetic ordering in solids are presented and many examples are given. Crystalline-electric-field effects are treated at a level that is sufficient to provide the basic knowledge necessary in understanding the properties of materials in which these effects play a role. Itinerant-electron magnetism is presented on a similar basis. Particular attention has been given to magnetocrystalline magnetic anisotropy and the magnetocaloric effect. Also, the usual techniques for magnetic measurements are presented. About half of the book is devoted to magnetic materials and the properties that make them suitable for numerous applications. The state of the art is presented of permanent magnets, high-density recording materials, soft-magnetic materials, Invar alloys and magnetostrictive materials. Many references are given.




先进磁性材料的纳米尺寸效应(21世纪科技前沿丛书先进磁性材料手册第1卷)


Book Description

本书共分四卷,第一卷集中论述一个具体的研究领域。每一章首先对该章的基本概念和重要观念进行阐述,然后从实验和理论方面进行详细的说明,最后介绍该领域的发展前景以及新的思想。




Handbook of Advanced Magnetic Materials


Book Description

In December 2002, the world's first commercial magnetic levitation super-train went into operation in Shanghai. The train is held just above the rails by magnetic levitation (maglev) and can travel at a speed of 400 km/hr, completing the 30km journey from the city to the airport in minutes. Now consumers are enjoying 50 GB hard drives compared to 0.5 GB hard drives ten years ago. Achievements in magnetic materials research have made dreams of a few decades ago reality. The objective of the four volume reference, Handbook of Advanced Magnetic Materials, is to provide a comprehensive review of recent progress in magnetic materials research. Each chapter will have an introduction to give a clear definition of basic and important concepts of the topic. The details of the topic are then elucidated theoretically and experimentally. New ideas for further advancement are then discussed. Sufficient references are also included for those who wish to read the original work. In the last decade, one of the most significant thrust areas of materials research has been nanostructured magnetic materials. There are several critical sizes that control the behavior of a magnetic material, and size effects become especially critical when dimensions approach a few nanometers, where quantum phenomena appear. The first volume of the book, Nanostructured Advanced Magnetic Materials, has therefore been devoted to the recent development of nanostructured magnetic materials, emphasizing size effects. Our understanding of magnetism has advanced with the establishment of the theory of atomic magnetic moments and itinerant magnetism. Simulation is a powerful tool for exploration and explanation of properties of various magnetic materials. Simulation also provides insight for further development of new materials. Naturally, before any simulation can be started, a model must be constructed. This requires that the material be well characterized. Therefore the second volume, Characterization and Simulation provides a comprehensive review of both experimental methods and simulation techniques for the characterization of magnetic materials. After an introduction, each section gives a detailed description of the method and the following sections provide examples and results of the method. Finally further development of the method will be discussed. The success of each type of magnetic material depends on its properties and cost which are directly related to its fabrication process. Processing of a material can be critical for development of artificial materials such as multilayer films, clusters, etc. Moreover, cost-effective processing usually determines whether a material can be commercialized. In recent years processing of materials has continuously evolved from improvement of traditional methods to more sophisticated and novel methods. The objective of the third volume, Processing of Advanced Magnetic Materials, is to provide a comprehensive review of recent developments in processing of advanced magnetic materials. Each chapter will have an introduction and a section to provide a detailed description of the processing method. The following sections give detailed descriptions of the processing, properties and applications of the relevant materials. Finally the potential and limitation of the processing method will be discussed. The properties of a magnetic material can be characterized by intrinsic properties such as anisotropy, saturation magnetization and extrinsic properties such as coercivity. The properties of a magnetic material can be affected by its chemical composition and processing route. With the continuous search for new materials and invention of new processing routes, magnetic properties of materials cover a wide spectrum of soft magnetic materials, hard magnetic materials, recording materials, sensor materials and others. The objective of the fourth volume, Properties and Applications of Advanced Magnetic Materials, is to provide a comprehensive review of recent development of various magnetic materials and their applications. Each chapter will have an introduction of the materials and the principles of their applications. The following sections give a detailed description of the processing, properties and applications. Finally the potential and limitation of the materials will be discussed.




Inorganic Materials Chemistry Desk Reference


Book Description

The updated second edition of the popular Inorganic Materials Chemistry Desk Reference remains a valuable resource in the preparation of solid-state inorganic materials by chemical processing techniques. It also expands upon new chemical precursors available to materials scientists, the applications of those materials, and existing or emerging topi




Advanced Topics in Materials Science and Engineering


Book Description

This volume contains the papers presented at the First Mexico-U.S.A. Symposium on Materials Sciences and Engineering held in Ixtapa, Guerrero, Mexico, during Septem ber 24-27, 1991. The conference was conceived with the primary objective of increas ing the close ties between scientists and engineers in both Mexico and the U.S. with an interest in materials. The conference itself would have not taken place without the drive, determination and technical knowledge of John K. Tien of the University of Texas at Austin and of Francisco Mejia Lira of the Universidad de San Luis Potosi. This book is dedicated to their memory. The event brought together materials scientists and engineers with interests in a broad range of subjects in the processing, characterization and properties of advanced materials. Several papers were dedicated to structural materials ranging from ferrous alloys to intemetallics, ceramics and composites. The presentation covered properties, processing, and factors that control their use, such as fatigue and corrosion. Other materials and properties were also explored by U.S. and Mexican participants. Sev eral papers dealt with the characterization and properties of magnetics, optical and superconductor materials, nanostructured materials, as well as with computational and theoretical aspects likely to impact future materials research and development.