Фазовая диаграмма системы Cr-Ta

К оглавлению: Другие диаграммы (Others phase diargams)


Cr-Ta (Chromium-Tantalum) M. Venkatraman and J.P. Neumann The assessed Cr-Ta phase diagram is based primarily on the work of [69Rud] and [73Koc]. The system is characterized by a single intermediate phase, Cr2Ta, which forms a eutectic with each of the terminal solid solutions, (Cr) and (Ta) . Cr2Ta melts congruently at 2020 с 20 C. The melting temperatures of Cr and Ta (1863 and 3020 C, respectively) have been adjusted to the IPTS-68. Cr2Ta exhibits two Laves phase modifications. The high-temperature form Cr2Ta ( HT) has the hexagonal MgZn2-type (C14) structure, whereas the low-temperature form Cr2Ta (LT) has the cubic MgCu2-type (C15) structure. The transformation between these two forms is sluggish, resulting in a wide range of reported transformation temperatures. [69Rud] indicated that the transformation temperature increases from 1660 C at the Cr-rich side to 1695 C at the Ta- rich side. 69Rud: E. Rudy, Tech. Rep. AFML-TR-65-2, 23, 137-141 (1969). 73Koc: Y.A. Kocherzhinskii, V.V. Petkov, and E.A. Shishkin, Metallofiz., 46, 75-80 (1973) in Russian. Published in Bull. Alloy Phase Diagrams, 8(2), Apr 1987. Complete evaluation contains 4 figures, 1 table, and 15 references. 1