Ferrites physical properties

Smit, J., Wijn, H. P. J. Ferrites Physical Properties of Ferrimagnetic Oxides in Relation to their Technical Applications, John Wiley, N.Y. Philips Tech. Libr., London 1959... 

Smit, J. and Wijn, H.P.J. (1959) Ferrites - physical properties of ferromagnetic oxides in relation to their technical applications, Philips Technical Library, The Netherlands. 

From Fig. 3.11, it can be seen that by increasing the chromium content while maintaining a limited amount of nickel-equivalent elements, first mixed martensite-ferrite structures are produced and then fully ferritic. This is 6-ferrite, that is a body-centred cubic structure stable at all temperatures. Relative to martensite it is soft, but it is also usually brittle. For this latter reason, usage has in the main been in small section form. This and some other disadvantages are offset for some purposes by attractive corrosion resistance or physical properties. 

In the ceramics field many of the new advanced ceramic oxides have a specially prepared mixture of cations which determines the crystal structure, through the relative sizes of the cations and oxygen ions, and the physical properties through the choice of cations and their oxidation states. These include, for example, solid electrolytes and electrodes for sensors and fuel cells, ferrites and garnets for magnetic systems, zirconates and titanates for piezoelectric materials, as well as ceramic superconductors and a number of other substances... 

Cubed compound, in PVC siding manufacture, 25 685 Cube lattice, 8 114t Cubic boron nitride, 1 8 4 654 grinding wheels, 1 21 hardness in various scales, l 3t physical properties of, 4 653t Cubic close-packed (CCP) structure, of spinel ferrites, 11 60 Cubic ferrites, 11 55-57 Cubic geometry, for metal coordination numbers, 7 574, 575t. See also Cubic structure Cubic symmetry Cubic silsesquioxanes (CSS), 13 539 Cubic structure, of ferroelectric crystals, 11 94-95, 96 Cubic symmetry, 8 114t Cubitron sol-gel abrasives, 1 7 Cucurbituril inclusion compounds,... 

Sodium ferrate, in sodium nitrite production, 22 855 Sodium ferrite, 14 543 Sodium fluoride, 22 825, 8 340 Sodium fluoroborate manufacture, 4 155 physical properties of, 4 152t thermodynamic properties of, 4 154t uses of, 4 156... 

Magnetic materials—control of oxygen composition and physical properties of Mn-Zn ferrites... 

Magnetic materials can be classified into two groups metal and alloy materials, and metal oxide materials represented by ferrites. We here describe the Mn-Zn ferrites, which are used, for example, as the magnetic heads in magnetic recording, focusing on the preparative processes and physical properties, which are closely related to the oxygen non-stoichiometry. 

Magnetic Recording Properties. Typical values of physical properties of barium ferrite pigments used in magnetic recording are given in Table 38. 

Nano-sized magnetic ferrite particles are the subject of intensive research because their physical properties are quite different from those of the bulk material. The magnetic characteristics of particles used for recording media crucially depend on their sizes and shapes. So, the material used for high-quality recording media should be ultrafme, chemically homogeneous, and stable, with a narrow particle size distribution a predetermined shape. These requirements demand a reliable and reproducible preparation technique. 

In contrast, synthetic investigations using PLD have been quite promising. h32 Recent studies of Mn cZni cFe204 have shown that crystalline films can be prepared on (100) oriented MgO substrates. Because the physical properties (e.g. resistivity and saturation magnetization) of this ferrite depend... 

Magnetite is a spinel ferrite which can be written as Fe [Fe Fe ]04. Unlike y-Fe203 it has no cation vacancies on the octahedral sites, but these sites contain equal numbers of Fe + and Fe + ions. A transition in many of its physical properties takes place between 110 and 120 K, and Verwey postulated a fast electron-transfer process (electron hopping) between the Fe + and Fe ions on the octahedral B sites above this temperature. The low-temperature form has discrete valence states and orthorhombic symmetry. 

Ferrites are complex because they combine two complex areas ceramic microstructures and magnetic phenomena. Ceramic microstructures, formed as a result of physico-chemical processes such as solid-state sintering, are affected by a large number of interacting variables the essentially quantum-mechanical nature of their magnetic properties makes them difficult to comprehend, since they are entirely different to macroscopic, every-day experience. The approach to ferrites their synthesis/fabrication the relationship between crystal structure, texture and physical properties the modelling of magnetic interactions, is of necessity interdisciplinary. 

Yavuz, Ozlem M. K. Ram, M. Aldissi, P. Poddar, S. Hariharan, Synthesis and the Physical Properties of MnZn Ferrite and NiMnZn Ferrite-Polyaniline Nanocomposite Particles. /. Mater. Chem. 2005, J5,810. 

Ceramic materials can present a wide set of physical properties e.g. ferro-electricity, pyroelectricity, piezoelectricity and ferromagnetism). The main class of ceramic material which exhibits magnetic properties is the class of ferrites. 

In Table 3.1-49 the chemical composition of a number of ferritic stainless steels is given. The most common representative is the grade X6Crl7/AISI 430. Table 3.1-50 presents some information on hot deformation and recommended heat treatment parameters. Tables 3.1-51 and 3.1-52 show typical data of the mechanical and physical properties, respectively, and Table 3.1-53 reviews the weldability of these steels. 

Table 3.1-52 Physical properties of ferritic stainless steels...

Table 3.1-57 Physical properties of martensitic and martensitic-ferritic chromium steels...

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