Ternary alloy structure

Lipson (1943, 1944), who had examined a copper-nickeMron ternary alloy. A few years ago, on an occasion in honour of Mats Hillert, Cahn (1991) mapped out in masterly fashion the history of the spinodal concept and its establishment as a widespread alternative mechanism to classical nucleation in phase transformations, specially of the solid-solid variety. An excellent, up-to-date account of the present status of the theory of spinodal decomposition and its relation to experiment and to other branches of physics is by Binder (1991). The Hillert/Cahn/Hilliard theory has also proved particularly useful to modern polymer physicists concerned with structure control in polymer blends, since that theory was first applied to these materials in 1979 (see outline by Kyu 1993). 

Figure 5. Schematic structure (left) of a ternary alloy on Ru(0 0 1) surface, MPt2/Ru, with M selected from the set Fe, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Snj.The two bottom layers represent Ru atoms while Pt atoms form the top surface atoms. The predicted surface activities of various ternary alloys are shown in the plot (right). (Reprinted from Ref [102], 2003, with permission from American Chemical Society.)...

An extension of the application of these maps to the systematic description of certain groups of ternary alloys has been presented also by Pettifor (1988a, b). Composition averaged Mendeleev numbers can be used, for instance, in the description of pseudo-binary, ternary or quaternary alloys. All these maps show well-defined domains of structural stability for a given stoichiometry, thus making the search easier for new ternary or quaternary alloys with a particular structure type (and which, as a consequence, may have the potential of interesting properties and applications (Pettifor 1988a, b)). 

Hetero-atomic clusters, moreover, may be derived from the binary structures mainly through the introduction of late transition or earlier post-transition elements. Examples of ternary alloys containing such structures are the alkali metal salts of centred clusters In10Me10 (Me = Ni, Pd, Pt), Tl12 Me12- (Me = Mg, Zn, Cd, Hg), etc. The crystal structure of the phase Na T Cdi x)27 (0.24 < x < 0.33)... 

These different interrelated structures, with special attention to their occurrence in Al-X-Y ternary alloys (X = Ti, Zr, Hf, V, Nb, Ta, Mo Y = V, Cr, Mn, Fe, Co, Ni, Cu, Zn) have been considered by Kumar (1990). According to differences in chemical bonding, mechanical and physical properties, Kumar considered (for various stoichiometries) three main groups of structures ... 

Y. Zhang, Y. Tsushio, H. Enoki, E. Akiba, The hydrogen absorption-desorption performances of Mg-Co-X ternary alloys with BCC structure, J. Alloys Compd. 393 (2005) 185-193. 

There are other factors to be considered. In a number of systems ternary phases exist whose stability indicates that there are additional, and as yet unknown, factors at work. For example, in the Ni-Al-Ta system r, which has the NisTi structure, only exists as a stable phase in ternary alloys, although it can only be fully ordered in the binary system where it is metastable. However, the phase competes successfully with equilibrium binary phases that have a substantial extension into the ternary system. The existence of the ly-phase, therefore, is almost certainly due to... 

In this Datareview, the crystalline quality of GaN and also of ternary alloys on GaN, which have wurtzite structure, characterised by a triple-axis high resolution X-ray diffraction system, is reviewed. 

Multicomponent and complex nanoparticle structures have been designed. For instance, Pt22V35Fe43 ternary alloy nanoparticles have been synthesized by... 

It became obvious that long-term stability of high surface area electrocatalysts was as important, or even more important than short-term activity. Luczak36 and Landsman pioneered the heat treatment of ternary alloy electrocatalysts in order to provide an ordered crystallite structure. This work was followed in Japan by Itoh and Katoh, and subsequently by... 

However, Mg2Si has a rather unfavorable, dense-packed crystal structure and shows no hydrogen interaction under moderate conditions (300 °C, 50 bar H2 150 °C and 100 bar [36]). Attempts have been made to modify the crystal structure or to partly substitute Si by ternary alloying additions, however, up to now, only with very limited success. 

Mizutani et al ° carried out a review of some of the problems of metal-lubricant composites, and in particular the difficulty caused by the fact that sintering temperatures are limited by the thermal stability of the lubricant. The result of this is that either softer metals must be used, or lower sintering temperatures which result in lower structural strength due to brittleness. This led them to investigate metal-lubricant composites in which the lubricant is synthesised in situ. The result was the ternary alloy of iron, molybdenum and sulphur which was described in Chapter 9, and which had the characteristics of a slightly sulphur-depleted molybdenum disulphide composite. 

Ohide T. Ohira G., The solidification structures of iron-carbon-phosphorous ternary alloys. Brit. Foundryman, 68 (1975) 4, 106-115... 

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