Фазовая диаграмма системы Mg-Ti

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Mg-Ti (Magnesium-Titanium) J.L. Murray There is very little mutual solubility of Mg and Ti in any phase, and no intermetallic compounds occur in the system. Most of the experimental work has concerned the solubility of Ti in liquid and solid Mg. The solubilities of Mg in (bTi) and (aTi) below 1200C were investigated by [55Fre] and [59Obi] and solid solubility estimates were given by [68Fin]. There is agreement [49Aus, 53Eis, 68Fin] that the solubility of Ti in solid ( Mg) is greater than in liquid at the Mg melting point and, therefore, that there is a peritectic reaction L + (aTi) = (Mg). The peritectic temperature was reported to differ from the Mg melting point by no more than 0.5 C [49Aus] and 1 C [68Fin]; both determinations were made by thermal analysis. For determination of the liquidus, only analysis of the composition of the saturated liquid has been found to be a suitable method [68Fin, 49Aus, 59Obi, 53Eis]. The data of [68Fin] are preferred, because equilibrium at each temperature was approached from above and below, and no difference in solubilities was found. The (Mg) solvus is based on electrical resistivity data of [68Fin]. On the Ti-rich side, estimates of the solubility of Mg were made by [55Fre], [ 59Obi], and [68Fin]. By chemical analysis of particles extracted from liquid Mg, [68Fin] reported 2.6 at.% Mg as the solubility of Mg in (bTi) at 1400 C. Based on metallographic work, [55Fre] found at least 2.9 at% Mg to be soluble in both (bTi) and (aTi) near 882C. According to [59Obi], the maximum observed solubility is 1.2 at.% Mg in (bTi) at 1200 C. The higher estimates [55Fre, 68Fin] are preferred; they must, however, be considered rough estimates only and of unknown accuracy. 49Aus: K.T. Aust and L.M. Pidgeon, Metall. Trans., 185, 585-587 (1949). 53Eis: H. Eisenreich, Metall, 7, 1003-1006 (1953) in German. 55Fre: J.W. Fredrickson, Trans. AIME, 203, 368 (1955). 59Obi: I. Obinata, Y. Takeuchi, and R. Kawanishi, Metall, 13, 392-397 (1959) in German. 68Fin: L.C. Fincher and D.H. Desy, Trans. AIME, 242, 2069-2073 (1968). Published in Phase Diagrams of Binary Magnesium Alloys, 1988, Phase Diagrams of Binary Titanium Alloys, 1987, and Bull. Alloy Phase Diagrams, 7(3), Jun 1986. Complete evaluation contains 2 figures, 3 tables, and 6 references. Special Points of the Ti-Mg System