Basic Magnetic Properties

The rare earth-cohalt magnets are discussed here with a fairly applied bias. Relevant fundamental subjects are treated exhaustively elsewhere in this handbook series basic magnetic properties of the RE-elements by Legvold (1980), those of RE-TM intermetallics by Buschow (1980), and the theory of hard-magnetic behavior - small-particle magnetization reversal, domain-wall nucleation and motion, and the role of anisotropy in these - by Zijlstra (1982). Buschow (1988) discusses the various mechanisms thought to be controlling the coercivity in all REPM, and the... 

In terms of basic magnetic properties, a ferro- or ferrimagnetic substance is a candidate for permanent magnet use when it fulfills the following three conditions (discussed in CGS system terminology) ... 

Basic magnetic properties of compounds of interest for RE-Co magnets [room-temperature values (except Tc)]. Data for single-crystal and powder samples. The experimental data are taken mostly from the following review papers Ervens (1979, 1982a,b), Narasimhan (1986), Nagel (1980), Kirchmayr and Poldy (1979), Stmat (1972b) and references cited therein. 

The basic magnetic properties expected in soft magnets are high initial and maximum permeabilities, p-, and r,., and low coercivity, (lower than 10 A/m). In many applications, soft magnets are subjected to ac fields their frequency response and, particularly, their ac losses are therefore important. 

The basic magnetic properties of R intermetaUics were reviewed by Kirchmayr and Poldy (1979). This review is of course in part outdated by now. A more recent review is provided by Gignoux and Schmitt (1995). Gratz and Zuckermaim (1982) give a compilation of transport properties of R intermetaUics. The field of An intermetaUics has been reviewed by Fournier and Troc (1985). A comparison of transport properties of selected R and An intermetaUics is given by Fournier and Gratz (1993). EspeciaUy the Ce and U intermetallic compoimds comprise the field of heavy-fermion and other strongly electron-correlated materials. Special reviews are dedicated to them, and we deal with them separately in sect. 9, where the major reviews for those compounds are fisted. 

CeAs. In general, the basic magnetic properties of CeAs are considered to be understood. As we shall see, there are strong hints from the (xSR data that the situation... 

The basic magnetic properties of ferrites have been described previously by Neel [45]. The magnetic properties of ferrites are due to interactions between the two sublattice magnetizations - the sublattice of magnetic moments of cations... 

Basic magnetic properties of metallic systems and materials are treated by Gignoux in [3.1]. Extensive data on magnetic properties of metals can be found in [3.2]. Magnetic properties of ferrites are treated by Guillot in [3.3]. Extensive data on magnetic and other properties of oxides and related compounds can be found in [3.4] and [3.5]. 

The magnetic properties of oxides and related compounds have been tabulated in comprehensive data collections [3.4]. A review of the basic magnetic properties of garnets (A3 [B2](Si3)Oi2 and spinel ferrites Me0Fc203 or Me Fe 04 is given by Guillot in [3.3]. 

Table 4.3-55 shows the basic magnetic properties of hard magnetic ferrites. The properties of actual products are shown in Fig. 4.3-77. The demagnetization curves of type YBM-9B, which have the best magnetic properties, are shown in Fig. 4.3-78. 

This chapter provides a description of the most common magnetic materials used in electrical engineering and other industrial applications. The first section details the physical quantities used to describe the magnetic properties of materials, while the following sections describe the basic magnetic properties of the five classes of magnetic materials. 

A reverse-micelle technique k considered an efficient route to produce high quality, monodisperse magnetic and superparamagnetic nanoparticles. It has been shown that the basic magnetic properties such as coercivity (He), saturation magnetization (Ms), Curie temperature (Jc) as well as lattice constank can be tuned by varying the cation stoichiometry [109]. In thk method, cation occupancy, elemental composition. 

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