Phase Diagrams, Intermetallic Phases and Compounds

Phase Diagrams, Intermetallic Phases and Compounds 7.3.3.I.2. Magnesium Systems. 

Equilibrium conditions for the synthesis of intermetallic phases and compounds are summarized as a function of temperature and composition in the form of phase diagrams. Consequently, in the following subsections, phase relationships for group-IIA-group-IB metal systems are reviewed. Phase diagrams in ref. 1 are used as a baseline work published before this compilation is not specifically referred to, but that reported subsequently is used, as appropriate, to modify or replace these phase diagrams. 

The sole interest in the chemistry of species containing group-IIA-group-IIB element bonds is metallurgical. Tne available data on phase equilibria have been reviewed and a handbook of phase diagrams published . Furthermore, structural data for intermetallic phases and compounds have been critically assessed . ... 

INTERMETALLIC PHASES AND COMPOUNDS 3.3.1 Potential versus mole fraction diagrams... 

Figure A1.37 shows the iron-carbon phase diagram up to 6.7 wt% carbon (to the first intermetallic compound, FejC). Of all the phase diagrams you, as an engineer, will encounter, this is the most important. So much so that you simply have to learn the names of the phases, and the approximate regimes of composition and temperature they occupy. The phases are ...

Note that the attainment of saturation concentrations does not mean the establishment of equilibrium between the solid and liquid phases because the reaction of formation of intermetallic or other compounds continues to proceed. However, the values found coincide with equilibrium ones which are obtained as an intersection of the lines of constant ratio of dissolving elements, coming out of the corner of the solvent, with the liquidus line of the isothermal section of the phase diagram. 

Sandrock, G. D. Reilly, J. J. and Johnson, J. R., Interrelations Between Phase Diagrams and Hydriding Properties for Alloys Based on the Intermetallic Compound FeTi, "Applications of Phase Diagrams in Metallurgy and Ceramics", National Bureau of Standards SP-496, 1977, 483. 

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