Ternary systems solidification

Although the activity obtained by the MA route was not the highest in this case, the effectiveness of MA was still much higher than that of conventional catalyst. In some cases, MA is more effective than rapid solidification for making supersaturated precursors. An example is the Al-Co-Cu ternary system (11). The ranking of effectiveness of these methods may in general depend on the alloy system. 

Str] Straube, H., Bloech, R., Ploeckinger, E., Dependence of Carbon Distribution in Ternary System Iron-Chromium-Carbon on Crystal Segregation Due to Solidification (in German), Metall, 29(2), 130-137 (1975) (Phase Diagram, Phase Relations, Experimental, 33) [1976Cho] Choudary, U.V., Belton, G.R., Thermodyn. of the Iron-Chromium-Carbon Melts at 1630° C , J. Metals, 28(12), A33 (1976) (Thermodyn., Abstract, 0)... 

Approximate isotherms at 50°C interval are superimposed in Fig. 10. In both Al-Fe and Fe-Si binary systems, depending on the alloy composition, either (aFe) or 02 may be the primary crystallization product. In the ternary system, as an approximation, the composition domains of (aFe) and 02 as primary crystallization products are delineated by the linear extrapolation between the composition limits of two binary edges. This is shown by a dashed line in Fig. 10. In the Fe-Si system, ai is the primary crystallization product during solidification of alloys containing 27.5 to 32 at.% Si. However, the extension of this composition range into the ternary system is not known. 

On continued cooling of the system both the components, A and C, will crystallize simultaneously and the composition of the melt will move on the boundary line ei —et until the ternary eutectic point et is attained, where also the component B begins to crystallize. At the eutectic temperature the system has no degree of freedom (k = 3, / = 4, V = 0), which means that its cooling will stop. The system maintains the eutectic temperature until its whole solidification. Completely analogical is the crystallization process of mixtures lying in the crystallization fields of the components B and C. 

Since C and Si are the alloying elements which dominate the solidification behavior and the resulting microstructures of cast irons, their phase equilibria need to be taken into account. Figure 3.1-120 shows a section through the metastable ternary Fe—C—Si diagram at 2wt%Si which approximates the Si content of many cast irons. Compared to the binary Fe—C system, the addition of Si decreases the stability of FesC and increases the stability of ferrite, as indicated by the expansion of the a-phase field. With increasing Si concentration, the C concentrations of the eutectic and the eutectoid equilibria decrease while their temperatures increase. 

The lead-free solder alloys attracting the greatest attention are the tin-rich alloys based on the tin-silver (Sn-Ag) and tin-copper (Sn-Cu) systems and their ternary alloys, Sn-Ag-Cu [3-5]. Numerous studies have been reported on Sn-Ag-Cu near-ternary alloys investigating processing and mechanical property behavior, and also their solidification characteristics [6-9]. 

Snugovsky, L. Perovic, D.D. Rutter, J.W. Solidification of ternary eutectic and near-eutectic alloys in the Ag-Cu-Sn system, presented at TMS Meeting, (San Diego, CA), March 2003. 

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