Phase relation in the titanium-rich region of the Ge-Si-Ti ternary system
Journal
Materials Transactions
Journal Volume
40
Journal Issue
4
Pages
307-313
Date Issued
1999
Author(s)
Abstract
The Ti-rich region of the Ge–Si–Ti ternary isotherm at 900°C was determined by metallography, X-ray diffraction, and electron microprobe analysis. The sample alloys were prepared by arc-melting. It was confirmed that at 900°C Ti5Si3 and Ti5Ge3 form a continuous solid solution Ti5(Si1−xGex)3 with the hP16 crystal structure. The lattice constants for Ti5(Si1−xGex)3 are linear functions of the composition variable x. This continuous solid solution also exists at 1100°C. There is another solid solution Ti3(Si1−yGey), that has the same crystal structure as Ti3Si (tP32), but this solid solution is stable only for y≤0.44 at 900°C. It was also shown that there is not any other binary or ternary phase within the Ti–Ti5Si3–Ti5Ge3 triangular region except Ti5(Si1−xGex)3 and Ti3(Si1−yGey). In this region, there is one three-phase field Ti+Ti5(Si1−xGex)3+Ti3(Si1−yGey), and the compositions of these three phases are Ti0.96Si0.03Ge0.01, Ti0.63Si0.08Ge0.29, and Ti0.75Si0.14Ge0.11 respectively. In addition, there are three two-phase fields within this region: Ti5(Si1−xGex)3+Ti3(Si1−yGey), Ti+Ti3(Si1−yGey), and Ti+Ti5(Si1−xGex)3.
Publisher
Japan Inst of Metals, Sendai
Type
journal article