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利用扩散偶局部平衡原理，通过金相观察和电子探针微区成分分析，测定了１０００℃下Ｔｉ－Ａｌ－Ｄｙ三元系部分等温截面相图。结果表明，该系在１０００℃存在２个三元相Ｄｙ（ＡｌｘＴｉ１－ｘ）２和Ｄｙ２·（ＡｌｘＴｉ１－ｘ）。在所测部分等温截面相图中存在６个单相区，８个两相平衡区，４个三相平衡区。１０００℃下Ｄｙ在γ（ＴｉＡｌ）和α２（Ｔｉ３Ａｌ）相中的固溶度随γ（ＴｉＡｌ）和α２（Ｔｉ３Ａｌ）的成分而变，其最大固溶度分别为０．７ａｔ％和０．２ａｔ％；而１０００℃下Ｄｙ在以ＴｉＡｌ２和ＴｉＡｌ３为基的固溶体中，含量均小于０．１ａｔ％。
Based on the principle of diffusion partial even, the isothermal cross-sectional phase diagram of Ti-Al-Dy ternary system at 1000 ℃ was measured by metallographic observation and electron probe micro-composition analysis. The results show that there are two ternary Dy (AlxTi1-x) 2 and Dy2 · (AlxTi1-x) at 1000 ℃. There are six single-phase zones, eight two-phase equilibrium zones and four three-phase equilibrium zones in the measured isothermal section phase diagram. The solid solubility of Dy in γ (TiAl) and α2 (Ti3Al) phases varies with the composition of γ (TiAl) and α2 (Ti3Al) at 1000 ℃. The maximum solubility of Dy is 0.7at% and 0.2at %. However, the content of Dy in TiAl2 and TiAl3-based solid solution at 1000 ℃ is less than 0.1at%.