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系统研究了热处理对Ｔｉ－５Ａｌ－１．５Ｎｄ，Ｔｉ－５Ａｌ－４Ｓｎ－１．５Ｎｄ（质量分数，％）两种钛合金中析出相长大规律的影响．结果表明，含Ｎｄ的钛合金的快凝态基体中分布着大量近球状的析出相，并沿晶体的晶界、亚晶界、位错线等处呈串状析出．在６５０－８００℃温度范围内经不同时间热处理后，析出相逐渐聚集长大，但长大速度都很慢．Ｔｉ－５Ａｌ－１．５Ｎｄ合金中析出相为立方的Ｎｄ_２Ｏ_３，其长大激活能为１１７ｋＪ／ｍｏｌ．加入Ｓｎ后，析出相的分布更加弥散，析出相中Ｎｄ和Ｓｎ的平均原子比为１．３７：１，经衍射花样的标定，判定为正交的Ｎｄ_５Ｓｎ_４，其长大速度更慢，长大激活能为１７０ｋＪ／ｍｏｌ．
The effects of heat treatment on the precipitation regularity of Ti-5Al-1.5Nd, Ti-5Al-4Sn-1.5Nd (mass fraction,%) titanium alloys were systematically investigated. The results show that a large number of near-spherical precipitates are present in the rapidly solidified matrix of the Nd-containing titanium alloy, and are precipitated in series along grain boundaries, subgrain boundaries and dislocation lines. In the 650-800 ℃ temperature range after heat treatment at different times, the precipitated phase gradually gathered to grow, but the growth rate is very slow. Ti-5Al-1.5Nd alloy precipitation phase cubic Nd_2O_3, the activation energy of its growth was 117kJ / mol. After Sn is added, the distribution of precipitated phase is more dispersed. The average atomic ratio of Nd and Sn in the precipitated phase is 1.37: 1. After the diffraction pattern is calibrated, Nd_5Sn_4, which is orthogonally determined, grows more slowly and grows The activation energy is 170 kJ / mol.