Фазовая диаграмма системы Gd-Pb

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Gd-Pb (Gadolinium-Lead) A. Palenzona and S. Cirafici The assessed Gd-Pb phase diagram is based on [69Dem]. The a = b transformation temperature of Gd has been changed to agree with the currently accepted values. The equilibrium phases are (1) the liquid, L; (2) six intermediate phases- Gd5Pb3, Gd5Pb4, Gd11Pb10, Gd6Pb7, GdPb2, and GdPb3; and (3) three terminal solid solutions, (aGd),(bGd),and (Pb). Addition of Pb to Gd gives rise to a catatectic equilibrium and to two solid solutions whose extention has been determined from microphotographs of several alloys quenched from 108C (aGd) or from thermal data (bGd). Despite the very good melting point of the Gd used, the a <259> b transformation is 23C higher than the accepted value. Sometimes, in such cases, it has been proposed to correct by a smiliar extent the transformation temperature of the pure metal and the catatectic equilibrium. However, because experimental reliable data are lacking, it was preferred to maintain the original catatectic equilibrium at the reported temperature. The melting point of lead was raised about 1C by Gd additions yielding a peritectic reaction determined by using a pure Pb sample as reference against an alloy at 97.44 at.% Pb. X-ray diffraction experiments showed the solubility of Gd in Pb to be less than 0.5 at.%. An exhaustive investigation of the systematics of the RE-Pb compounds was given in [71Gsc]. 60Ian: A.Iandelli, Atti Accad. Naz. Lincei Rend. Cl. Sci. Fis., Mat. Nat., 29, 62-29 (1960) in Italian. 64Kuz: Yu. B. Kuzma, R.V. Skolozdra, and V.Ya. Markiv, Akad. Nauk. Ukr. RSR, 8, 1070-1072 (1964) in Russian. 66Pal: A. Palenzona and M.L. Fornasini, Atti Accad. Nazl. Lincei. Rend. Cl. Sci. Fis., Mat. Nat., 40, 1040-1044 (1966) in Italian. 67Jei: W. Jeitschko and E. Parthe, Acta Crystallogr., 22, 551-555 (1967). 69Dem: J.T. Demel and K.A. Gschneidner, Jr., J. Nucl. Mater., 29, 111-120 ( 1969). 69Mer: F. merlo and M.L. Fornasini, Atti Accad. Nazl. Lincei, Rend. Cl. Sci. Fis., Mat. Nat., 46, 265-269 (1969) in Italian. 71Gsc: K.A. Gschneidner, Jr. and O.D. McMasters, Monatsh. Chem., 101, 1499- 1515 (1971) in German. Submitted to the APD Program. Complete evaluation contains 1 figure, 5 tables, and 12 references. Special Points of the Gd-Pb System