Ferrites solid solution

Figure 5.29. Fe-rich region of the Fe C phase diagram. Stable Fe-C (graphite) diagram solid lines metastable Fe-Fe3C diagram dashed lines. The following current names are used ferrite (solid solution in aFe), austenite (solid solution in 7Fe) and cementite (Fe3C compound). Pearlite is the name given to the two-phase microstructure which originates from the eutectoid reaction ...

Ferrite Solid solution of carbon in alpha iron (bcc). 

A THE OXIDATION BOUNDARY FOR MAGNETITE-ZINC FERRITE SOLID SOLUTIONS... 

Oxidation Boundary for Magnetite-Zinc Ferrite Solid Solutions... 

The area ADE represents the region of stability of 8-ferrite the area DEF the region in which 8-ferrite solid solutions and y-ferrite solid solutions are in equilibrium and the area AEB is the area for 8-solid solutions and molten mixtures. 

Pearlite (mixture of ferrite (solid solution of C in a-Fe) and cementite, Fe3C) Reheat... 

Iron Low-carbon steels Low-carbon alloy steels Decarburised malleable Chromium 980-1 050 (Halide) 1. Gaseous 2. Semi- gaseous 3. Pack 25-75 urn Solid-solution (ferritic) 20-25% Cr Ductile (200-300 HV) Weldable Heat treatment acceptable ... 

Ferrite the body-centred cubic form of iron (a-iron) and the solid solutions of one or more elements in b.c.c. iron. 

NOTE Steel consists of ferrite and pearlite phases. Ferrite is a solid solution of carbon in iron, whereas pearlite is a mixture of ferrite and laminar cementite. Cementite is a carbide, such as ferric carbide (Fe3C), although part of the iron content may be replaced by other metals including molybdenum. 

Ferrite is introduced into the aqueous media by two techniques. With the in situ method, ferrite is formed within the actinide-containing solution by addition of Fe(II), Fe(III), and sodium hydroxide. With the preformed ferrite method, ferrite solids are prepared separately and added to the actinide solution. 

By forming solid solutions between two ferrites, it is possible to tune the properties magnetically. An example is provided by the solid solution Zn,Ni1 xFe204, which is between the normal spinel ZnFe2C>4 and the inverse spinel NiFe2C>4. Reaction to form a solid solution with NiFe2C>4 ... 

Garnet ferrites, 11 55, 56t, 57 Gamet-hydrogarnet solid solution series, 5 479t... 

The material properties used in the simulations pertain to a new X70/X80 steel with an acicular ferrite microstructure and a uniaxial stress-strain curve described by er, =tr0(l + / )", where ep is the plastic strain, tr0 = 595 MPa is the yield stress, e0=ff0l E the yield strain, and n = 0.059 the work hardening coefficient. The Poisson s ratio is 0.3 and Young s modulus 201.88 OPa. The system s temperature is 0 = 300 K. We assume the hydrogen lattice diffusion coefficient at this temperature to be D = 1.271x10 m2/s. The partial molar volume of hydrogen in solid solution is... 

Carbon is soluble to varying degrees in each of these allotropic forms of iron. The solid solutions of carbon in a-Fe, y-Fe, and <5-Fe are called, respectively, ferrite, austenite, and 8-ferrite. So, for example, the single-phase region labeled as y in... 

Energy losses in soft magnetic materials arise due to both hysteresis and eddy currents, as described in the previous section. Eddy current losses can be reduced by increasing the electrical resistivity of the magnetic material. This is one reason why solid-solution iron-silicon alloys ( 4% Si) are used at power frequencies of around 60 Hz and why iron-nickel alloys are used at audio frequencies. Some magnetically soft ferrites (see Section 6.2.2.1) are very nearly electrical insulators and are thus immune to eddy current losses. Some common soft magnetic materials and their properties are listed in Table 6.19. Soft magnetic alloys are described further in Section 6.2.1.6. 

The best-known eutectoid reaction is that which occurs in steel where the austenite phase, stable at high temperatures, transforms into (he eutectoid structure known as pcarlitc In this transformation, the austenite phase, containing 0.8% carbon in solid solution, transforms to a mixture of ferrite (nearly pure body-centered cubic irom anti iron-carbide (Fe-.Ct. Al atmospheric pressure, the equilibrium temperature for this reaction is 723 C. This temperature is the eutectoid temperature... 

In binary alloy systems, a eutectoid alloy is a mechanical mixture of two phases which form simultaneously from a solid solution when it cools through Ihe eutectoid temperature. Alloys leaner or richer in one of the metals undergo transformation from the solid solution phase over a range of temperatures beginning above and ending al the eutectoid temperature. The structure of such alloys will consist of primary particles of one of the stable phases in addition to ihe eutectoid. lor example ferrite and pearlite in low-carbon steel. See also Iron Metals, Alloys, and Steels. 

Waychunas, G. A. Mossbauer. X-Ray. Optical, and Chemical Study of Cation Arrangement and Defect Association in Fm3m.Solid Solutions in the System Periclae-Wustite-Lithium Ferrite Ph.D. Thesis U.C.L.A., Los Angelos, 1981. 

Fig. 2.5 Part of the system CaO-AljOj-FejOj. Hatched lines indicate solid solutions. Ferrite phase compositions are indicated by the quantity x, which relates to the formula CajfAl Fe, After Newkirk and Thwaite (N8) and Majumdar...

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