Magnetism and magnetic materials

... discussion of some basic features of magnetism In the first part a brief survey will therefore be given of the origin of magnetic moments, the most common types of magnetic ordering, and molecular field ... Chapter 14 Soft -Magnetic Materials 14.1 Introduction 14.2 Survey of Materials 14.3 The Random-Anisotropy Model 14.4 Dependence of Soft -Magnetic Properties on...

Ngày tải lên: 17/03/2014, 13:39

... characterize magnetic properties of such Co /InP nanocomposites at 300 K with magnetic field sweeping from -15 to 15 KOe Results and discussions Structure characterization of Co /InP nanocomposites ... 47.39°, and 75.89° correspond to hexagonal Co (100), (002), (101), and (110), respectively This further confirms that the obtained sample is that of Co /InP nanocomposites...

Ngày tải lên: 21/06/2014, 04:20

... Technologies of Rare-Earth-Based Magnets 12 .7 Hard Ferrites 12 .8 Alnico Magnets References 10 5 10 5 10 6 10 9 11 2 11 5 11 9 12 2 12 4 12 8 Chapter 13 High-Density Recording Materials 13 .1 Introduction 13 .2 Magneto-Optical ... Recording Materials 13 .3 Materials for High-Density Magnetic Recording References 13 1 13 1 13 3 13 9 14 5 CONTENTS vii Chapter 1...

Ngày tải lên: 12/08/2014, 01:21

... between the J = 5 /2 and J = 7 /2 levels but also due to a difference in energy separation between the levels of the J = 5 /2 manifold (g = 2/ 7 and the levels of the J = 7 /2 manifold (g = 52/ 63) Generally ... violation of the Curie law (Eq 3 .2. 3) Exper­ imental results for demonstrating this exceptional behavior are shown in Fig 3 .2. 1 16 CHAPTER PARAMAGNETISM OF FREE IONS...

Ngày tải lên: 12/08/2014, 01:21

... 32 CHAPTER THE MAGNETICALLY ORDERED STATE field dependence of the magnetization behaves as shown by curve (a) in Fig 4 .3. 3 The slope of the first part of this curve is given ... Lett., 36 , 532 Slater, J C (1 930 ) Phys Rev., 35 , 509; Phys Rev., 36 , 57 Sommerfeld, A and Bethe, H (1 933 ) in H Geiger and K Scheel (Eds) Handbuch der physik, Berlin: Springer, Vol 24, Part 2, .....

Ngày tải lên: 12/08/2014, 01:21

... average of is not obtained when we apply a magnetic field to the situation shown in Fig 5.2.2 The magnetic field will lift the degeneracy of each of the three doublet levels Since a given magnetic ... application of a magnetic field, a current is induced in such a direction that the corresponding magnetic field opposes the applied field For obtaining expressions by means of...

Ngày tải lên: 12/08/2014, 01:21

... Consequently, a magnetic field of is the magnetic field in an infinitely long solenoid consisting of n turns per meter of coil and carrying an electric current of The unit of the magnetic induction or magnetic ... equals a magnetic field strength of in free space corresponds to a mag­ netic induction of or, equivalently, a magnetic induction of T corresponds to a...

Ngày tải lên: 12/08/2014, 01:21

... IN MAGNETIC MATERIALS In the absence of the magnetic field, the 2J + energy states of each of the participating magnetic moments are degenerate For a system which contains N non-interacting magnetic ... of a magnetic field will lift the degeneracy of each of the N manifolds of 2J + states It follows from Fig 3.1.1, and also from Eq (3.1.1), that the energy separation...

Ngày tải lên: 12/08/2014, 01:21

... descriptions of magnetic anisotropy and its determination can be found in the textbooks of Chikazumi (1966) and McCaig and Clegg (19 87) References Chikazumi, S (1966) Physics of magnetism, New ... reversal is the existence of magnetic- domain structures Magnetic particles of sufficiently large size will generally not be uniformly magnetized but rather be composed of magn...

Ngày tải lên: 12/08/2014, 01:21

... 2 29, p 197 Suzuki T ( 198 4) IEEE Trans Magn., 20, 675 This page intentionally left blank 14 Soft -Magnetic Materials 14.1 INTRODUCTION Soft -magnetic materials are mainly used in magnetic cores of ... two or more types of anisotropy are parallel A survey of the anisotropy in various Fe-based soft -magnetic materials has been presented by Soinski and Moses ( 199 5) 14.2 SUR...

Ngày tải lên: 12/08/2014, 01:21

... polycrystalline alloys and offer the possibility of tailoring superior soft -magnetic properties for specific applications In Fig 14.2.8, the soft -magnetic properties of various groups of materials are compared ... dependence of the magnetic properties of various types of soft -magnetic materials is compared in Fig 14.4.1 The random-anisotropy model apparently provides a...

Ngày tải lên: 12/08/2014, 01:21

... susceptibility, 113 magnetically ordered state, 19 magnetic anisotropy, 97 magnetic cores, 147 magnetic entropy, 94 magnetic- induction heads, 159 magnetic losses, 109, 147 magnetic- ordering, 21 magnetic ... nanocrystalline soft -magnetic materials, 155, 158 119 permanent magnets, 119 Néel temperature, 27 Ni–Fe alloys, 149 nucleation field, 113 nucleation of Bloch walls,...

Ngày tải lên: 12/08/2014, 01:21

... MICRO- RAMAN STUDY OF MECHANICALLY ACTIVATED FERROELECTRICS AND ADVANCED MAGNETIC MATERIALS YU TING (B Sc Jilin University) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY ... presents results of our micro- Raman studies of mechanically activated ferroelectrics, PbTiO3 & SrBi2Ta2O9, and advanced magnetic materials, CoFe2O4 & CrO2 The mecha...

Ngày tải lên: 17/09/2015, 17:19

... signs to the magnetic effects: paramagnetism and diamagnetisme Strong magnetic effects in ferromagnetic materials 4/1/2008 Weak magnetic effects in paramagnetic materials in diamagnetic materials ... Chapter XII Magnetic materials §1 Atomic magnetic moment - Bohr magneton §2 Magnetization, paramagnetism and diamagnetism §3 Ferromagnetism 4/1/2008  Investigation of the...

Ngày tải lên: 21/12/2013, 03:15

... addition of Co2+ ion content, which may be attributed to the ionic radii of constituent ions causing increase in lattice parameter and the densities of pure cobalt ferrite (5.29 g/cm3) and pure nickel ... temperature.These plots show that an increase in Co2+ doping yields monotonic increase in the saturation magnetization of Niferrite which may be due to the substit...

Ngày tải lên: 13/02/2014, 04:20