Metal iron aluminides

Rabin, B. H., and Wright, R. N., Synthesis of iron aluminides from elemental powders reaction mechanisms and densification behavior. Metall. Trans. A, 22A, 277 (1991). 

The metal activity of iron aluminides is about two orders of magnitude higher than that of nickel aluminide, as can be seen in Fig. l.The higher metal activity results in a higher thermodynamical stability of iron aluminides. 

Selective solution of the aluminum from the alloy using a volatile metal, such as mercury, lead, bismuth, cadmium, magnesium, or zinc, has been investigated. After extracting the aluminum from the original alloy into the volatile metal, the volatile metal is distilled, leaving pure aluminum. Neither electrolysis nor volatile metal extraction can extract aluminum from iron aluminide [12004-62-5], FeAl, titanium aliiminide [12004-78-3], TiAl, or Al C. ... 

The powder selected for this category is a coarse (-270 mesh) inter-metallic compound iron aluminide or FeAl. This powder is extremely difficult to process into a thin sheet therefore, tape casting is an ideal way to produce the precursor sheet, which is then sintered and rolled to final density. 

Fie] Field, R.D., Zindel, J.W., Fraser, H.L., The Intercellular Phase in R idly Solidified Alloys Based on the Al-Fe System , Scr. Metall, 20,415-418 (1986) (Crys. Stracture, Experimental, 8) [1987Die] Diehm, R.S., Mikkola, D.E., Effects of Mo and Ti Additions on the High Temperature Compressive Properties of Iron Aluminides Near FcsAl , Mater. Res. Soc. Symp. Proc. High-Temp. Ordered Intermetallic Alloys II, 81,329—334 (1991) (Experimental, Phase Relations, Meehan. Prop., 8)... 

McK] McKamey, C.G., Horton, J.A., The Effect of Molybdenum Addition on Properties of Iron Aluminides , Metall. Trans. A., 20A, 751-757 (1989) (Experimental, Phase Relations, Meehan. Prop., 16)... 

And] Anderson, I.M., Alehemi Study of Site Distributions of 3rf-Transition Metals in 52-Ordered Iron Aluminides , Acta Mater., 45(9), 3897-3909 (1997) (Calculation, Crys. Structure,... 

Lee and Lin (1999) studied the oxidation, mixed oxidation-sulphidation and hot corrosion of ductile iron aluminide Fe3Al with Cr addition at temperatures of 605-800°C. They observed that hot corrosion of iron aluminide was significantly more severe than oxidation and mixed oxidation-sulphidation. According to Lee and Lin, this can be attributed to the formation of aluminium sulphide at the metal-salt interface as a result of high sulphur potential in the molten salt at the oxide-metal interface. 

Paramount information on structure and phase equilibria of the ThMni2 type compounds was collected by Gladyshevsky et al. (1990), while the structure and magnetic properties have been reviewed several times for rare-earth aluminides (Nowik and Felner 1983), rare-earth and actinide aluminides (Suski 1985), actinide aluminides (Sechovsky and Havela 1988), intermetallics with higher content of the iron-group metals for the rare eardis (Buschow 1991, H.-S. Li and Coey 1991), and uranium (Suski 1992). 

Although a wide range of materials has been considered as anode materials for SOFC (14), most developers today use a cermet of nickel and YSZ. Early on in the development of SOFC, precious metals such as platinum and gold were used, as well as pure transition metals such as nickel and iron. Because of the physical and chemical instability of these materials, other materials such as nickel aluminide were tested. 

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