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研究了Ｔｉ－２４Ａｌ－ｌｌＮｂ合金中Ｔｉ３Ａｌ＋Ｎｂ金属间化合物在甲醇溶液中的应力腐蚀及室温氢致开裂的规律，探讨了组织结构的影响．结果表明，Ｔｉ３Ａｌ＋Ｎｂ在甲醇溶液中应力腐蚀敏感性很高，不向组织应力腐蚀断裂归一化门槛值为而ｋ（ＩＳＣＣ）／ＫＣ＝０．５３－０．６９；应力腐蚀裂纹止裂门槛值为Ｋ（ＩＳＣＣ）／Ｋ（ｌｉ）＝０．６１－０．７９．Ｔｉ３Ａｌ＋Ｎｂ在室温动态充氢时能发生氢致开裂，门槛值和应力腐蚀相近，但裂纹扩展速率或断裂时间比应力腐蚀要慢１－３个数量级．两者断口形貌也不相同．发现了相界应力腐蚀现象．对固溶后炉冷试样，当ＫＩ较低时，应力腐蚀裂纹优先沿α２／β相界形核和扩展，从而获得相界应力腐蚀断口．如固溶后空冷或ＫＩ较高，则不出现相界应力腐蚀．
The stress corrosion of Ti3Al + Nb intermetallic compounds in Ti-24Al-llNb alloy and the cracking induced by hydrogen at room temperature were studied, and the influence of microstructure was also discussed. The results show that the stress corrosion resistance of Ti3Al + Nb in methanol solution is very high, and the normalized threshold value of stress corrosion cracking without fracture is k (ISCC) /KC=0.53-0.69. The threshold value of stress corrosion cracking K (ISCC) / K (li) = 0.61-0.79. Hydrogen-induced cracking occurs when Ti3Al + Nb is dynamically charged at room temperature. The threshold value is similar to stress corrosion, but the crack growth rate or fracture time is 1-3 orders of magnitude slower than that of stress corrosion. Both fracture appearance is not the same. Found the phase boundary stress corrosion phenomenon. When the KI is low, the stress corrosion cracking preferentially crosses the α2 / β phase boundary nucleus and expands, so as to obtain the phase boundary stress corrosion fracture. If the solution after air cooling or KI is high, there is no phase boundary stress corrosion.