Physics of Magnetism

92 CHAPTER 10. CALORIC EFFECTS IN MAGNETIC MATERIALS In writing down these equations, one has to realize that M depends on tempe ...

SECTION 10.2. THE MAGNETOCALORIC EFFECT 93 be estimated from measurements on nickel alloys that show no magnetic ordering. The t ...

94 CHAPTER 10. CALORIC EFFECTS IN MAGNETIC MATERIALS In the absence of the magnetic field, the 2J + 1 energy states of each of t ...

SECTION 10.2. THE MAGNETOCALORIC EFFECT 95 Consequently, when the field H is applied under isothermal conditions, the heat relea ...

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11 Magnetic Anisotropy Phenomenologically, the anisotropy A magnetic material is said to possess magnetic anisotropy if its inte ...

98 CHAPTER 11. MAGNETIC ANISOTROPY obtained in this way for several permanent-magnet materials by Strnat (1988) are shown in Fig ...

CHAPTER 11. MAGNETIC ANISOTROPY 99 Equating the two torques leads to the relation The value of H that makes parallel with the fi ...

100 CHAPTER 11. MAGNETIC ANISOTROPY where is the remanence in the hard direction and where the factor has been introduced to sim ...

CHAPTER 11. MAGNETIC ANISOTROPY 101 obtains In this case, In the face diagonal direction, [110], one obtains Substitution of th ...

102 CHAPTER 11. MAGNETIC ANISOTROPY The torque can be obtained by differentiating this equation: The torque expressions for uni ...

CHAPTER 11. MAGNETIC ANISOTROPY 103 McCaig, M. and Clegg, A. G. (1987) Permanent magnets in theory and practice, 2nd edn, London ...

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12 Permanent Magnets 12.1. INTRODUCTION showing a broad hysteresis loop and a concomitant high coercivity. The remanence determi ...

106 CHAPTER 12. PERMANENT MAGNETS 12.2. SUITABILITY CRITERIA The maximum energy product is one of the most generally used criter ...

SECTION 12.2. SUITABILITY CRITERIA 107 and will not be much different from each other when the former value is smaller than the ...

108 CHAPTER 12. PERMANENT MAGNETS ...

SECTION 12.3. DOMAINS AND DOMAIN WALLS 109 relevant parameter here is the maximum amount of mechanical work that can be obtained ...

110 CHAPTER 12. PERMANENT MAGNETS Let us consider the case that a steadily increasing magnetic field is applied in a direction o ...

SECTION 12.3. DOMAINS AND DOMAIN WALLS 111 if written as For two atoms with an angle between their spin moments, the variable pa ...