作者:K.H. Zhang、J.M. Yin
DOI:10.1016/j.jallcom.2006.12.019
日期:2008.4
A vertical section at 33.3 at.% Y in the Au-Ag-Y ternary system was studied using X-ray diffraction analysis, differential thermal analysis, and optical microscopy. An allotropic phase transformation of the Au2Y phase in the Au-Y binary system is found. The Au2Y phase transforms from a room temperature phase a to a high-temperature modification beta at about 778 degrees C. The alpha-Au2Y has a tetragonal MoSi2-type structure with the lattice parameters a = 0.3692 nm, c = 0.8981 nm; the beta-Au2Y has an orthorhombic CeCu2-type structure with the lattice parameters a = 0.4658 nm, b = 0.7340 nm, and c = 0.8200 nm. No allotropic phase transformation of the Ag2Y phase in the Ag-Y binary system is found. The vertical section of the Au2Y-Ag2Y in the Au-Ag-Y ternary phase diagram established on the basis of these studies consists of seven phase regions: L (liquid phase region), alpha (MoSi-type structure), beta (CeCu2-type structure), alpha + beta, alpha + L, beta + L, and alpha + beta + L. (C) 2006 Elsevier B.V. All rights reserved.