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
The plastic deformation behavior of γ-TiAl(Ti-56%Al) single crystals was studied by compression in the temperature range of-196-1100℃ along seven crystal orientations: [001],[152] , [021], [233], [191], [251] and [110]. The profile of the yield stress-temperature curves measured can be divided into three parts: in the temperature range of-196-600℃, the yield stress first decreases rapidly with increasing temperature followed by a plateau above room-temperature.The yield stress then shows an anomalous increase with increasing temperature above 600 ℃and reaches a peak between 700-1000℃, depending on crystal orientations. Above the peak temperature, the yield stress again decreases rapidly with increasing temperature. Below the peak temperature, the deformation mode is {111}<110] ordinary slip only for [021] orientation and {111}<101] superlattice slip for other orientations. Above the peak temperature, the deformation modes are: {111}<112] twinning, {111}<112] superlattice slip or ordinary slip. The planes for ordinary slip can be {111}, {110) or (001), depending on crystal orientations.
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| [4] |
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