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Alloys single-phase binary

A system which can easily be treated in this way is a single phase binary alloy. For preparation, however, let us consider an A crystal with a vacancy flux driven across it. In view of the fact that jA +y v = 0 in the steady state lattice system, the vacancy flux induces a counterflux of A, which shifts the whole crystal in the direction of the surface where the vacancy source is located. The shift velocity vb is yV... [Pg.185]

For a single-phase binary alloy A-B, the two anodic partial reactions of metal dissolution are... [Pg.156]

We will study and follow only single-phase binary alloys (with two components) for which it was possible to set up some models, which already show the complication of the phenomena compared to oxidation of pirre metals. [Pg.606]

For these single-phase binary alloys we can distinguish four modes of oxidations, which differ from each other by the nature and the localization of oxidized phases ... [Pg.607]

Selective oxidation of single-phase binary metal alloys... [Pg.607]

Consider a single-phase binary alloy (Al, A2) forming a sohd solution of substitution of two metals Al and A2. One carries out the oxidation of this alloy by a gas G2 under conditions such as only the Al element is oxidized to form on the surface of alloy a layer of the oxidized compound AIG. It is said that Al tmdergoes a selective oxidation. That will be, for example, the case of nickel-platimtm alloys with selective oxidation of nickel into NiO, example of which is used [KUB 49], [LAL 73], [THO 49], [WAG 52] to model selective oxidation as we will see further. We suppose that the gas imdergoes a dissociative adsorption. [Pg.607]

Oxidation of single-phase binary alloys with miscibility offormed oxides... [Pg.630]

The use of a percolation approach clarifies substantially the selective dissolution of single-phase binary alloys. Computer simulations support the existence of a tight relationship between dealloying thresholds and site percolation thresholds. However, a careful survey of the literature over the last 10 years leads to the striking constatation... [Pg.205]

Ni-Cr and Co-Cr alloys are typical single-phase binary alloys. Ni-6Cr, Ni-8Cr, Co-5Cr and Co-lOCr alloys were selected to study the first type of transition between external and internal oxidation under atmospheres with ultra-low oxygen partial pressures Pq in which the solvent Ni or Co in the alloys does not oxidize [14,19]. [Pg.43]

The phase diagram for a binary alloy (Fig. A1.13) shows single-phase fields (e.g. liquid) and two-phase fields (e.g. liquid plus A). The fields are separated by phase boundaries. When a phase boundary is crossed, a phase change starts, or finishes, or both. [Pg.336]

In contrast, the selective dissolution or leaching-out by corrosion of one component of a single-phase alloy is of considerable practical importance. The most common example of this phenomenon, which is also referred to as parting , is dezincification, i.e. the selective removal of zinc from brass (see Section 1.6). Similar phenomena are observed in other binary copper-base alloys, notably Cu-Al, as well as in other alloy systems. [Pg.48]

The general thermodynamic treatment of binary systems which involve the incorporation of an electroactive species into a solid alloy electrode under the assumption of complete equilibrium was presented by Weppner and Huggins [19-21], Under these conditions the Gibbs Phase Rule specifies that the electrochemical potential varies with composition in the single-phase regions of a binary phase diagram, and is composition-independent in two-phase regions if the temperature and total pressure are kept constant. [Pg.363]

Because of the interest in its use in elevated-temperature molten salt electrolyte batteries, one of the first binary alloy systems studied in detail was the lithium-aluminium system. As shown in Fig. 1, the potential-composition behavior shows a long plateau between the lithium-saturated terminal solid solution and the intermediate P phase "LiAl", and a shorter one between the composition limits of the P and y phases, as well as composition-dependent values in the single-phase regions [35], This is as expected for a binary system with complete equilibrium. The potential of the first plateau varies linearly with temperature, as shown in Fig. 2. [Pg.368]

Iridium-rhodium alloys were prepared in electric arc furnace in argon atmosphere by smelting refined powders of rhodium and iridium of 99.95 mass% purity. The composition of the alloys was controlled by the atomic adsorption analysis using the Perkin-Elmer spectrophotometer with HUS-72 analyzer. X-ray phase analysis indicated that all binary systems had a single-phase FCC-structure characteristic of... [Pg.507]

Fig. 12.4. Schematic illustration of conserved and nonconserved order parameters for characterizing the internal state of a binary alloy (adapted from Chen and Wang (1996)) (a) disordered phase (rj = 0) with uniform composition cq, (b) two-phase mixture consisting of disordered phases (rj = 0) with composition Cq, and c, (c) ordered single phase (ri = 1) of single composition ci with an antiphase domain boundary. Fig. 12.4. Schematic illustration of conserved and nonconserved order parameters for characterizing the internal state of a binary alloy (adapted from Chen and Wang (1996)) (a) disordered phase (rj = 0) with uniform composition cq, (b) two-phase mixture consisting of disordered phases (rj = 0) with composition Cq, and c, (c) ordered single phase (ri = 1) of single composition ci with an antiphase domain boundary.

See other pages where Alloys single-phase binary is mentioned: [Pg.232]    [Pg.156]    [Pg.126]    [Pg.1854]    [Pg.726]    [Pg.750]    [Pg.158]    [Pg.158]    [Pg.206]    [Pg.3]    [Pg.57]    [Pg.139]    [Pg.17]    [Pg.47]    [Pg.302]    [Pg.172]    [Pg.383]    [Pg.100]    [Pg.172]    [Pg.37]    [Pg.76]    [Pg.1538]    [Pg.28]    [Pg.369]    [Pg.38]    [Pg.179]    [Pg.521]    [Pg.1537]    [Pg.142]    [Pg.13]   
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