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金属间化合物ＴｉＡｌ是极有发展前景的新一代高温结构材料，其Ｒ现象受到广泛研究。首先根据固体与分子经验电子理论（ＥＥＴ）由ＢＬＤ方法计算了ＴｉＡｌ的价电子结构，然后通过分析位错在ＴｉＡｌ（１１１）面上滑移前后原子排列关系的变化，由键能公式近似计算了三种平面缺陷ＡＰＢ，ＣＳＦ和ＳＦ的能量。据此分析了ＴｉＡｌ的Ｒ现象的内在机制。结果表明，由于ＴｉＡｌ的ＡＰＢ能量远大于ＳＦ的，ＴｉＡｌ的Ｒ现象不可能是单一Ｋ—Ｗ位错交滑移钉扎机制独立所为，因温度激活导致的孪生交割钉扎机制也有很大的贡献。
Intermetallic TiAl is a promising new generation of high temperature structural materials, and its R phenomenon has been widely studied. Firstly, the valence electron structure of TiAl was calculated by the BLD method according to the solid and molecular empirical electronic theory (EET). Then by analyzing the variation of atomic arrangement before and after sliding on the TiAl (111) surface, the bond energy formula Three planar defects APB, CSF and SF energy. Based on this, we analyze the inherent mechanism of R phenomenon in TiAl. The results show that since the APB energy of TiAl is far greater than that of SF, the Ti phenomenon of TiAl can not be independently controlled by a single K-W dislocation cross-slip pinning mechanism. The twinning pinning mechanism due to temperature activation is also very large contribution.