Permanent Magnet Materials And Their Application

Comprehensive design text for permanent magnets and their application.

Magnetic Materials and their Applications discusses the principles and concepts behind magnetic materials and explains their applications in the fields of physics and engineering. The book covers topics such as the principal concepts and definitions related to magnetism; types of magnetic materials and their electrical and mechanical properties; and the different factors influencing magnetic behavior. The book also covers topics such as permanent-magnet materials; magnetic materials in heavy-current engineering; and the different uses of magnetic materials. The text is recommended for physicists and electrical engineers who would like to know more about magnetic materials and their applications in the field of electronics.

Permanent magnets play an increasingly important role in modern society because they are vital components of numerous domestic and industrial devices. The last few decades have witnessed a quite extraordinary development in the use of hard magnetic materials, especially after the advent of rare earth permanent magnets. The rare earth permanent magnets are unequalled because they combine a high magnetization with an extraordinary magnetic hardness which allows the use of such magnets having the extreme shapes and small dimensions as required in modern devices.

Modern Permanent Magnets provides an update on the status and recent technical developments that have occurred in the various families of permanent magnets produced today. The book gives an overview of the key advances of permanent magnet materials that have occurred in the last twenty years. Sections cover the history of permanent magnets, their fundamental properties, an overview of the important families of permanent magnets, coatings used to protect permanent magnets and the various tests used to confirm specifications are discussed. Finally, the major applications for each family of permanent magnets and the size of the market is provided. The book also includes an Appendix that provides a Glossary of Magnetic Terms to assist the readers in better understanding the technical terms used in other chapters. This book is an ideal resource for materials scientists and engineers working in academia and industry R&D. Provides an in-depth overview of all of the important families of permanent magnets produced today Includes background information on the fundamental properties of permanent magnets, major applications of each family of permanent magnets, and advances in coatings and coating technology Reviews the fundamentals of permanent magnet design

Covering the design and applications of permanent magnets, this study lists properties of over 400 materials and presents diverse magnet information needed to design products rather than present theory. Appendices provide demagnetisation curves and magnetic/physical properties.

This book treats permanent magnet (hard) materials, magnetically soft materials for low-frequency applications and for high-frequency electronics, magnetostrictive materials, superconductors, magnetic-thin films and multilayers, and ferrofluids. Chapters are dedicated to magnetic recording, the role of magnetism in magnetic resonance imaging (MRI), and instrumentation for magnetic measurements.

The book provides both the theoretical and the applied background needed to predict magnetic fields. The theoretical presentation is reinforced with over 60 solved examples of practical engineering applications such as the design of magnetic components like solenoids, which are electromagnetic coils that are moved by electric currents and activate other devices such as circuit breakers. Other design applications would be for permanent magnet structures such as bearings and couplings, which are hardware mechanisms used to fashion a temporary connection between two wires.This book is written for use as a text or reference by researchers, engineers, professors, and students engaged in the research, development, study, and manufacture of permanent magnets and electromechanical devices. It can serve as a primary or supplemental text for upper level courses in electrical engineering on electromagnetic theory, electronic and magnetic materials, and electromagnetic engineering.

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.