Preface

Summary

The original inspiration to write this book came when, after an electrical engineering training in the late 1960s, I embarked upon the design of a variety of permanent magnet electrical machines. I needed to know more about the behavior and performance of the different magnet materials than the electromechanical design texts provided, and significantly more applications data than the scientific books on magnetism contained. This shortcoming was exacerbated in the early 1970s when an entirely new class of magnet - the rare earths - was discovered, offering a vast array of new opportunities for permanent magnet devices, and new challenges to designers such as myself. As these new materials were developed, their properties exhibited dramatic improvements from year to year, reaching maturity in the early 1990s as a full range of samarium-cobalt and neodymium-iron-boron magnets. Until this had happened, I felt that any attempt to produce a comprehensive text including a description of these materials would have been premature. Now, with first-hand experience in most cases, I am able to describe their selection and design for a wide range of important applications.

The material for this book has evolved from courses given to students and practicing engineers while I was at the University of Cambridge and the University of Southern California, and from a variety of assignments to develop and design permanent magnet materials.