Liquidus phase relation

The basic process was to melt the powder completely and then cool it to observe the crystaUized phases in order to estabhsh the liquidus phase relations. The crucibles were suspended in the thermal center of a resistance furnace from which the crucibles could be dropped into water of room temperature. Samples were heated to 1580 °C and held for 3 h for complete melting and then were cooled down by different methods. The first method was continuous cooling from 1580 °C to room temperature. In this way, the whole process of crystalHzation was completed, thus the phases representing the crystallization path could be obtained. In order to confirm the crystallization sequence of the obtained phases in the continuously... 

DTA experiments indicated a second transition zone 0 + a occurs between 1710 10 °C (X-phase) and 1575 15 °C (Y-phase). Finally a continuous liquidus-solidus relation characterizes the high-temperature a-solid solution series with melting temperatures of 1770 10 °C (X-phase) and 1700 35 °C (Y-phase). Melting experiments performed with various X—Y phase mixed crystals resulted in inhomogeneous quenched products. Since a small vapor loss could hardly be prevented, some exsolved molybdenum metal was always observed. 

The authors have described some fundamental procedures to evaluate the solid-liquid phase relations of nano-sized particles in binary alloys from the calculation of the surface properties as well as the phase equilibira on the basis of thermodynamic databases, which are usually used for the calculation of phase diagrams of the bulk materials. In order to obtain quantitatively precise values of the melting points and liquidus temperatures in alloys, we should carry out further investigation as follows ... 

For metaluminous systems, apatite crystallizes relatively early in the crystallization sequence of felsic magmas, and crystallizes comparatively later in more mafic melts. For example, it was estimated that apatite is a near liquidus phase in the Johnson Granite Porphyry, but began to crystallize after about 1/3 of the Kuna Crest (quartz diorite) magma crystallized (Piccoli and Candela 1994). Ultimately, apatite often first appears as an intercumulus phase in gabbros and related rocks (e g., Boudreau et al. 1986). 

Yam] Yamada, A., Umeda, T., Determination of Liquidus and Sohdus Surfaces for the Iron rich Comer of the Fe-Cr-Ni System and its Application to Calculating Phase Diagram in Soli-dif. Proc. 8T Proc. 3rd Int. Conf, Sheffield, Sept. 21-24 1987, 485-487 (1988) (Experimental, Phase Relations, Calculation, 6)... 

Hil] Hillert, M., Qiu, C., A Reassessment of the Cr-Fe-Ni System , Met. Trans. A, 21(6), 1673-1680 (1990) (Assessment, Calculation, Phase Diagram, Phase Relations, 40) [1990Yam] Yamada, A., Umeda, T., Kimura, Y, Calculation of Liquidus and Solidus Surfaces of the Iron Rich Comer of the Fe-Cr-Ni System , J. Iron Steel Inst. Jpn., 76(12), 2137-2143 (1990) (Calculation, Phase Diagram, Phase Relations, 25)... 

Mie] Miettinen, J., Howe, A.A., Estimation of Liquidus Temperatures for Steels Using Thermodynamic Approach , Ironmaking Steelmaking, 27(3), 212-227 (2000) (Calculation, Experimental, Phase Relations, Thermodyn., 53)... 

Gri] GrifEing, N.R., Forgeng, W.D., Healy, G.W., C-Cr-Fe Liquidus Surface , Trans. AIME, 224, 148-159 (1962) (Crys. Structure, Morphology, Phase Diagram, Phase Relations, Experimental, 14)... 

Jac] Jackson, R.S., The Austenite Liquidus Surface and Constitutional Diagram for the Fe-Cr-C Metastable System , J. Iron Steel Inst., London, 208(2), 163-167 (1970) (Phase Relations, Phase Diagram, Experimental, 36)... 

Tho] Thorpe, W.R., Chicco, B., The Fe-Rich Comer of the Metastable C-Cr-Fe Liquidus Surface , Metall. Trans. A, 16A, 1541-1549 (1985) (Crys. Slracture, Morphology, Phase Relations, Experimental, 31)... 

Seh] Sehuermann, E., Sehweiniehen, J., Voelker, R., Fiseher, H., Caleulation of the a/6 resp -y-Liquidus of Iron and of the Liquidus of Carbon as well as of the Univariant Reaction Lines in Iron-Rich, Carbon Containing Three-Component and Multicomponent Fe-C-Xj-X2-Systems. MEMO (in German), Giessereiforschung, 39(3), 104-113 (1987) (Phase Diagram, Phase Relations, Thermodyn., Calculation, 19)... 

Wag] Wagner, C., Thermodynamic Analysis of the Liquidus in Ternary Systems Involving Small Contents of One Component , Metall Trans. B, 7B(3), 485-488 (1976) (Phase Diagram, Phase Relations, Thermodyn., 30)... 

Fen] Fenstad, J., Liquidus Relations and Thermoehemistry Within flie System Fe-Mn-C-0 , Thesis 2000 126 (2000 23) Dept. Mater. Elchem., NTNU, (2000) (Experimental, Phase Relations, Thermodyn.)... 

Elder data on phase relations were reviewed and critically assessed by Raynor and Rivlin [1988Ray], who in turn refer to several older reviews and assessments. They suggested best choice versions of liquidus projection, including position of tie-triangles for some solid-liquid monovariant equilibria, Scheil scheme and a number of isothermal sections for 1100 to 600°C. This assessment was updated by [1994Rag], who included literature up to 1991. 

Dur] Durisinova, D., Durisin, J., Repiska, L., Mathematical Description of Liquidus Surface in Fe-C-Mn System , Kovove Mater., 5, 547-560 (1988) (Phase Relations, Phase Diagram, Calculation, 22)... 

Schuster, J.C., Giron, G., Durand-Charre, M., On The Liquidus Surface Involving -y-Iron in the System Fe-Mo-C , Exp. Methods Phase Diagram Determ., Proc. Symp., 1993, 133-140 (1994) (Experimental, Phase Diagram, Phase Relations, Morphology, 9)... 

Danilenko, V.M., Rubaschevskii, A.A., Velikanova, T.A., Computer Calculation of Liquidus of Mo-Fe-C Phase Diagram (in Russian), Achivements in the Field of the Physical Material Science., Akad. Nauk. SSR., IPM, Kiev, 110-126 (1995) (Thermodyn., Phase Diagram, Phase Relations, 16)... 

Kongoli, F., McBow, L, Yazawa, A., Liquidus Surfaee of Lime Ferrite Slags at Intermediate Oxygen Potentials , Mater. Trans., 44(10), 2136-2140 (2003) (Phase Relations, Calculation, Phase Diagram, 22)... 

In order to investigate the full elastic constant tensor of iron at inner core conditions, Steinle-Neumann et al. (2001) combined first principles GGA density functional theory with the particle in a cell method. The crystallographic structure of iron was assumed to be hexagonal close-packed (hep). Experiments show that this is the low temperature high pressure phase of iron from 10 GPa, to at least 300 GPa, the highest pressures so far explored in static experiments (Mao et al. 1990). Experiments also show that hep is the liquidus phase to at least 100 GPa (Shen et al. 1998). There is theoretical evidence that hep is the stable phase of iron at the conditions of the Earth s inner core (Vocadlo et al. 1999). Experimental observations of other structures at high pressures and temperatures (Andrault et al. 1997 Saxena et al. 1995) have been controversial (Boehler 2000) the proposed structures are closely related to hep. 

In liquid phase epitaxial growth of compound semiconductor layers, the growth rate depends on the slope of the liquidus line and on the supercooling AT at the time of the initial contact between substrate and growth solution. This is another example that illustrates that the growth kinetics is determined by thermodynamic phase relations. 

Sch] Schiirmann, E., Schweinichen, J.V., Investigation of the Liquidus Equilibria of Iron Rich Carbon Containing Ternary Systems Fe-C-X with X = Al, Cu, Ni and Cr (in German), Giessereiforsch., 38, 125-132 (1986) (Review, Phase Relations, Phase Diagram, Experimental, 63)... 

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