Фазовая диаграмма системы Gd-Yb

К оглавлению: Другие диаграммы (Others phase diargams)


Gd-Yb (Gadolinium-Ytterbium) K.A. Gschneidner, Jr. and F.W. Calderwood The assessed phase diagram for the Gd-Yb system is based on the work of [74Bea] , who observed that the solubility of Yb in (Gd) ranges from 6.5 at.% at 500 C to 19 at.% at 1161 C. The addition of Yb lowers b (bcc) = a (cph) transformation temperature of Gd by catatectic reaction at 20 at.% Yb and 1161 C and lowers the melting point of Gd to a monotectic horizontal at 1183 C. This horizontal extends from 21 to 71 at.% Yb. Solid solubility of Gd in (Yb) ranges from 0.2 at.% at 500 C to 2.3 at.% at 822 C. [74Bea] also showed that the melting point of Yb was raised 3 C by the addition of Gd. The melting point of Yb was reported to be 3 C lower than the accepted value, and thus the melting point and the (gYb) peritectic horizontal have been increased by this amount in the assessed diagram. The addition of Gd to Yb also lowers the g (bcc) = b (fcc) transformation temperature from 795 to 780 C. Solubility of Gd in liquid Yb was found to be quite low, ranging from 1.6 at.% at 850 C to 12.3 at.% at 1150 C. The intermediate compositions in this system form two phases. The tendency to form trivalent Yb in (Gd) was small. 74Bea: B.J. Beaudry and F.H. Spedding, Metall. Trans., 5, 1631 (1974). Published in Bull. Alloy Phase Diagrams, 4(3), Nov 1983. Complete evaluation contains 1 figure and 2 references. 1