Фазовая диаграмма системы B-Pd

К оглавлению: Другие диаграммы (Others phase diargams)


B-Pd (Boron-Palladium) P.K. Liao and K.E. Spear The assessed Pd-B equilibrium phase diagram is based primarily on [82Alq], with additional data from [67Bro], [69Bro], [76Bro], and [78Spe]. The system consists of three intermediate compounds: Pd16B3, Pd3B, and Pd5B2. The existence of a higher boride phase reported by [59Leh], PdxBy, remains uncertain. For B content greater than 30 at.%, the liquidus and the invariant temperatures are rather uncertain. [82Alq] reported the phase relations of the Pd-B system containing up to 30 at. % B between 290 and 1450 C. Boron dissolves in Pd over a large range, which extends to 18.6 at.% at 1065 C. A miscibility gap below a critical temperature of 410 C exists in this solid solution region [68Hus]. Its width extends from 2.1 to 10.2 at.% B at 312 C. Pd16B3 is formed congruently from the solid solution at 397 C, and, together with the miscibility gap, a monotectoid reaction occurs. Pd3B is formed peritectoidally from (Pd) and Pd5B2 at 890 C. Pd5B2 melts congruently at 1115 C. The homogeneity ranges of these compounds are believed to be very narrow. There are no experimental results for compositions greater than 30 at.% B in this system. 54Kuo: K. Kuo and L.E. Persson, J. Iron Steel Inst. London, 178, 39, (1954). 59Leh: W.M. Lehrer, Trans. AIME, 215, 168-169 (1959). 61Ste: E. Stenberg, Acta Chem. Scand., 15, 861-870 (1961). 67Bro: H. Brodowsky and H.-J. Schaller, Ber. Bunsenges. Phys. Chem., 71(8), 926-927 (1967) in German. 68Hus: H. Husemann and H. Brodowsky, Z. Naturforsch., 23a, 1693-1694 (1968) in German. 69Bro: H.A. Brodowsky and H.-J. Schaller, Trans. Metall. Soc. AIME, 245, 1015- 1020 (1969). 70Car: J.O. Carlsson and T. Lundstrom, J. Less-Common Met., 22, 317-320 (1970). 70Mah: M. Mahnig and L.E. Toth, Phys. Lett., 32A(3), 319-320 (1970). 76Bro: H. Brodowsky and H.-J. Schaller, Ber. Bunsenges. Phys. Chem., 80(7), 656-661 (1976) in German. 78Spe: K.E. Spear, Applications of Phase Diagrams in Metallurgy and Ceramics, NBS Spec. Publ. 496, Vol. 2, 744-762 (1978). 82Alq: R.A. Alqasmi, H. Brodowsky, and H.-J. Schaller, Z. Metallkd., 73, 331- 334 (1982) in German. Submitted to the APD Program. Complete evaluation contains 4 figures, 2 tables, and 16 references. Special Points of the Pd-B System