铝化钛的反常强化行为和电子结构

Anomalous yield strengthening behavior (AYB) and electron structure in TiAl

由计算的铝化钛ＴｉＡｌ三种平面缺陷能在价电子结构层次分析了ＴｉＡｌ的反常屈服强化行为（ＡＹＢ）。结果表明，ＴｉＡｌ的ＡＹＢ不可能是单一Ｋ－Ｗ位错交滑移钉扎机制独力所为，而是三种主位错交互作用引起的；孪生交割钉扎机制也有很大作用；其本质原因是温度直接影响健结构导致的强化与弱化综合作用的结果。

Anomalous yield behavior (AYB) in TiAl is systematically studied in view of valence electron structure according to the empirical electron theory of solids and molecules (EET). On the basis of the calculation of three kinds of planar defects energies, AYB in TiAl is resulted from mutual actions of three main dislocations locking mechanisms because antiphase boundary energies are much more than simple fault ones, and twin intersection locking mechanism has a large effect on AYB. The natural reason of AYB in TiAl is that the variation of bond structure with temperature results in strengthening, and 'disorder damain' strengthening with descending of short distance ordered parameter has a main effect on AYB in TiAl.