Nickel phase diagram

Fig. 20.45 (a) Iron-rich end of the iron-nickel phase diagram and (ft) iron-rich end of the iron-... 

Pan Y.Y., Nash P., La-Ni (Lanthanum-Nickel) , Phase Diagrams of Binary Nickel Alloys, P. Nash, Ed., ASM International, Materials Park, OH. - 1991. -P. 183-188. 

Mar53] Margolin, H.,Ence,E., and Nielsen, J.P., Titanium-Nickel Phase Diagram, TY-ans. TMS-AIME, Vol 197, 1953, p. 243-247... 

Fig. 3. Liquidus isotherms of gold—cooper—nickel alloys and phase diagrams of the binary substituents (85).

Tables 1 and 2, respectively, Hst the properties of manganese and its aHotropic forms. The a- and P-forms are brittle. The ductile y-form is unstable and quickly reverses to the a-form unless it is kept at low temperature. This form when quenched shows tensile strength 500 MPa (72,500 psi), yield strength 250 MPa (34,800 psi), elongation 40%, hardness 35 Rockwell C (see Hardness). The y-phase may be stabilized usiag small amounts of copper and nickel. Additional compilations of properties and phase diagrams are given ia References 1 and 2.

Phase diagrams have been measured for almost any alloy system you are likely to meet copper-nickel, copper-zinc, gold-platinum, or even water-antifreeze. Some... 

Many stainless steels, however, are austenitic (f.c.c.) at room temperature. The most common austenitic stainless, "18/8", has a composition Fe-0.1% C, 1% Mn, 18% Cr, 8% Ni. The chromium is added, as before, to give corrosion resistance. But nickel is added as well because it stabilises austenite. The Fe-Ni phase diagram (Fig. 12.8) shows why. Adding nickel lowers the temperature of the f.c.c.-b.c.c. transformation from 914°C for pure iron to 720°C for Fe-8% Ni. In addition, the Mn, Cr and Ni slow the diffusive f.c.c.-b.c.c. transformation down by orders of magnitude. 18/8 stainless steel can therefore be cooled in air from 800°C to room temperature without transforming to b.c.c. The austenite is, of course, unstable at room temperature. Flowever, diffusion is far too slow for the metastable austenite to transform to ferrite by a diffusive mechanism. It is, of course, possible for the austenite to transform displacively to give... 

Aircraft turbines in jet engines are usually fabricated from nickel-based alloys, and these are subject to combustion products containing compounds of sulphur, such as S02, and oxides of vanadium. Early studies of the corrosion of pure nickel by a 1 1 mixture of S02 and 02 showed that the rate of attack increased substantially between 922 K and 961 K. The nickel-sulphur phase diagram shows that a eutectic is formed at 910 K, and hence a liquid phase could play a significant role in the process. Microscopic observation of corroded samples showed islands of a separate phase in the nickel oxide formed by oxidation, which were concentrated near the nickel/oxide interface. The islands were shown by electron microprobe analysis to contain between 30 and 40 atom per cent of sulphur, hence suggesting the composition Ni3S2 when the composition of the corroding gas was varied between S02 02 equal to 12 1 to 1 9. The rate of corrosion decreased at temperatures above 922 K. 

Wang JH and Liu M. Computational study of sulfur-nickel interactions A new S-Ni phase diagram. Electrochem Commun 2007 9 2212-2217. 

Gupta, K.P. Phase Diagrams of Ternary Nickel Alloys Parti and II. ASM International, Materials Park, OH, 1990. 

The successful conversion of graphite to diamond involves crystallizing the diamond from a liquid melt. The solvent most often used is nickel metal, or alloys of nickel with other ferrous metals. The reason for this success can be seen by referring to Figure 15.7, the binary (solid + liquid) phase diagram for (nickel + carbon).u8 We note from the figure that (Ni + C) forms a simple... 

We note from the phase diagram that some nickel remains dissolved in the diamond, but the amount is small, with mole fraction of carbon > 0.9998 at the eutectic temperature. Thus, diamond of reasonably high purity is obtained. At the present time, this and similar processes are used to produce large quantities of diamonds. The crystals are usually small and find most use in industrial grinding and cutting processes. 

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