Nb对Ti3Al价电子结构及其脆性的影响

应用固体与分子经验电子理论计算了Ti3Al及加入Nb后各相的价电子结构，并从均匀变形因子α、解理能Gc及位错行为等方面分析了Nb对Ti3Al脆性的影响。结果表明，Nb使α2相部分无序化，产生新的韧性相，提高了Ti3Al合金的α和Gc值；同时Nb也减弱了Ti-Ti共价键，增加了基面滑移，从而综合导致Ti3Al脆性有本质改善。

EFFECT OF Nb ON VALENCE ELECTRON STRUCTURES AND EMBRITTLEMENT OF Ti3Al

According to the E E T, the valence electron structures of the various phases in Ti-Al-Nb alloys are calculated. Effect of Nb on embrittlement of Ti3A1 is analysed in view of uniform deforming factor a, cleave enery Gc and dislocation movement. Analysis shows that Nb makes α2 partly disordered and novel phase toughened, and then a and Gc bigger. Ti-Ti bond weakened and dislocation slip increased in basis plane. As a result, embrittlement of Ti3A1 alloyed with Nb is naturally improved.