Intermetalhc compound

The systems obtained when galhum is in the presence of bismuth, cadmium, germanium, mercury, lead, sihcon, or thalhum present miscibihty gaps. No intermetalhc compounds ate formed. 

Betterton-KroIIProcess. MetaHic calcium and magnesium are added to the lead bullion in a melt and form ternary compounds that melt higher than lead and are lower in density. By cooling the lead bath to a temperature close to the melting point of lead, the intermetalHc compounds high in bismuth content soHdify and float to the top where they are removed by skimming. 

The electrodeposition of Cr in acidic chloroaluminates was investigated in [24]. The authors report that the Cr content in the AlCr, deposit can vary from 0 to 94 mol %, depending on the deposition parameters. The deposit consists both of Cr-rich and Al-rich solid solutions as weU as intermetalHc compounds. An interesting feature of these deposits is their high-temperature oxidation resistance, the layers seeming to withstand temperatures of up to 800 °C, so coatings with such an alloy could have interesting applications. 

A hi mi nidcs. These are intermetalhc compounds of aluminum. The potential of these products includes uses where low weight, high-temperature strength, and oxidation resistance are required. Traditionally, these products are made by way of powder metallurgy technology. 

Thermodynamics of Intermetalhc Compound-Hydrogen Systems, in Hydrogen in Intermetallic Compounds I (ed. L. Schlapbach), Springer Verlag, Berlin, p. 49. 

The numerous intermetalHc compounds of zirconium, from ZtAl to ZrZn j, are reviewed in References 120—123. 

Transition-element chalcogenides are also best prepared by direct reaction of the elements at 400-1000° C in the absence of air. They tend to be metallic nonstoichiometric alloys though intermetalhc compounds also occur, e.g. Ti...2Se, Ti-sSe, TiSeo.95, TiSei.os, Tio.gSe, Ti3Se4, Tio.vSe, TisSeg, TiSe2, TiSes, etc. ... 

Most barium compounds are not as thermodynamically stable as the corresponding compounds of magnesium and calcium and therefore can be reduced by these metals. However, rather than producing pure barium, barium alloys are formed. Barium combines with most metals, forming a wide range of alloys and intermetalhc compounds. Among the phase systems that have been better characterized are those with Ag, Al, Bi, Hg, Pb, Sn, Zn, and the other Group 2 metals (12). 

Fujiwara, T, Yasuda, K., Kodama, H. (1991), in Proc. Int. Symp. on IntermetalHc Compounds -Structure and Mechanical Properties (J1 MIS-6) Izumi, O. (Ed.). Sendai The Japan Institute of Metals, pp. 633-637. 

Hydrogen reduction of chlorides in thermal plasma can be apphed not only to produce powder of individual metals but also to produce different intermetalhc compounds. The composition of the generated crystals copies the composition of the chloride mixture in the gas phase. This effect permits the production of the intermetallic compounds with the required composition. Refractory intermetallic compounds based on niobium and vanadium were synthesized from their chlorides (conversion close to 100%) in a hydrogen plasma jet generated by RF-ICP discharge (Bashkirov Medvedev, 1968). The reaction products were crystallized on a substrate sustained at a temperature of about 1000°C. The plasma-metallurgical technology is proven to be effective in the synthesis of vanadium-Hsilicon... 

As the study progressed, it was noted that Pd is capable to form intermetalhc compounds such as PdgPbj and PdgTlj (i.e., PdgMj, M = Hg, Tl, Pb, Bi). In addition. 

Liu] Liu, S., Hamaguehi, Y, Kuwani, H., Intermetalhc Compounds and Their Formation Reactions in the System Fe-Cr-Mo at High Temperatures (in Chinese), Acta Metall. Sin., 25, B97-103 (1989) (Phase Diagrams, Experimental,, 15)... 

Li] Li, C., Chin, Y.L., Wu, R, Correlation between Bulk Modulus of Ternary Intermetalhc Compounds and Atomic Properties of their Constituent Elements , Intermetallics, 12, 103-109 (2004) (Meehan. Prop., Review, 24)... 

The ternary rare earth metal-transition metal-indium systems contain a vast number of individual intermetalhc compounds. In this section we summarize the crystallographic data (lattice parameters) of all known indides. The compounds are grouped with respect to the d element component. 

In 1961 a naval engineer, William J. Buechler, made an unexpected and fortunate discovery. In searching for the best metal to use in missile nose cones, he tested many metal alloys. One of them, an intermetalhc compound of nickel and titanium, NiTi, behaved very oddly. When he struck the cold metal, the sound was a dull thud. When he struck the metal at a higher temperature, however, it resonated like a beU. Mr. Buechler knew that the way in which sound propagates in a metal is related to its metallic structure. Clearly, the structure of the NiTi alloy had changed as it went from cold to warm. As it turned out, he had discovered an alloy that has shape memoiy... 

As the solder approaches its solidus temperature, the rate of intermetalhc compound formation decreases significantly and the solder joint is formed. It is critical that the solder freezes prior to circuit board handhng for two important reasons. First, accidental movement of the PWB may cause the components to move in the molten solder, which could result in defects such as solder joint opens (disbonds) or solder shorts (unwanted bridging of solder from one bond pad to the next). Second, a solder joint disturbance at the critical transition from liquid to solid may result in a bond of degraded reliability. This type of bond has an inherently grainy look and can even have microfractures within caused by motion-induced interruption of orderly crystal growth during solidification. 

When the electronegativity of composition elements in crystal compounds are close to each other and that of impure atoms lie between that of two composition elements, geometric factors hke atomic sizes etc. are the main factor if the doping process proceeds. For example, in various intermetalhc compounds or covalent ones, those atoms with close radius (differences no more than 15%) could substitute each other to form substituted impurity defects. 

Enthalpies and entropies of formation of intermetalHc compounds of Tl with rare earths and actinides... 

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