Фазовая диаграмма системы Ho-Tb

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Ho-Tb

Ho-Tb (Holmium-Terbium) K.A. Gschneidner, Jr. and F.W. Calderwood The assessed Ho-Tb phase diagram is based on the work of [73Spe]. Because the thermal arrests were within 1.5 C on both the heating and cooling curves, as with pure metals, the liquidus/solidus line and the solvus line for the bcc = cph transformation were drawn as single lines. The solidus and solvus merge, indicating a peritectic reaction. The transformation temperature of Tb was found to increase linearly by the addition of Ho, but at a greater slope than the melting temperature. Extrapolation of the transformation temperature curve to the solidus showed that the two curves intersect at 10 at.% Tb in (Ho). This confirmed the absence of a bcc form at high temperatures in Ho. [79Shi] applied the Kaufman approach to the calculation of the Ho-Tb phase diagram and compared their results to those obtained experimentally by [73Spe]. Their calculated peritectic point occurred at a somewhat lower temperature and Ho concentration than did the experimentally determined peritectic point. 73Spe: F.H. Spedding, B. Sandeen, and B.J. Beaudry, J. Less-Common Met., 31, 1 (1973). 79Shi: G.J. Shiflet, J.K. Lee, and H.I. Aaronson, Calphad, 3, 129 (1979). Published in Bull. Alloy Phase Diagrams, 4(3), Nov 1983. Complete evaluation contains 2 figures and 4 references. 1