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在-196-1100℃温度范围内，利用压缩试验研究了γ-TiAl单晶（Al的原子分数为56％）在[001]，[152]，[021]，[233],[191]，[251]，[110]七个晶体取向上的塑性变形行为、它们的屈服强度-温度关系曲线都可分成三个部分：-196-600℃屈服强度随温度的升高先是快速下降，达到室温附近以后基本保持不变；600℃以上，屈服强度随温度的升高而反常升高，随晶体取向的不同在700-1000℃之间达到峰值；峰温以上，屈服强度随温度的升高又呈现快速下降的趋势峰温以下仅[021]取向的形变方式为｛111｝＜110]普通位错滑移，其余皆为｛111｝＜101]超点阵位错滑移。峰温以上．形变方式为：｛111｝＜112]孪生变形、｛111｝＜112]超点阵位错滑移、或普通位错滑移，普通位错的滑移面随晶体取向的不同可以是｛111｝，｛110｝或（001）面
In the temperature range of -196-1100 ℃, the tensile properties of γ-TiAl single crystal (atomic ratio of Al is 56%) were studied by compressive test in [001], [152], [021], [233], [191] [251], [110] plastic deformation behavior of the seven crystal orientations, their yield strength - temperature relationship curve can be divided into three parts: -196-600 ℃ yield strength decreases rapidly with increasing temperature, reaching room temperature The temperature of 600 ℃ and above, the yield strength increases abnormally with the increase of temperature, and reaches the peak value with the difference of crystal orientation between 700-1000 ℃; when the temperature is above the peak temperature, the yield strength increases with the temperature The trend of rapid decline is only below the peak temperature. The deformation of [021] orientation is {111} <110] ordinary dislocation slip, and the rest are {111} <101] superlattice dislocation slips. Peak temperature above. The deformation modes are: {111} <112] twin deformation, {111} <112] superlattice dislocation slip, or ordinary dislocation slip. The slip plane of common dislocations may vary with crystal orientation {111 }, {110} or (001) plane