中文摘要：

利用从头算平面波赝势密度泛函理论方法研究了高压下L10-TiAl金属间化合物的结构和弹性性质．研究发现当压力在0-20GPa范围内时，c／a的值基本上保持-常数1．02，与实验结果吻合．当压力在20-45GPa范围内时，f／n的值随压力的增加从1．02线性减小到0．99．这表明在低压下沿f轴和沿a轴的压缩性是一样的，但是高压下沿c轴比沿口轴更容易压缩．计算了从0到20GPa压力下L10-TiAl的弹性常数．同时我们还计算了剪切各向异性比率A和Voigt剪切模量，与实验结果和别人的计算结果相吻合．

英文摘要：

The structural and elastic properties of L10-TiA1 intermetallics under high pressure are inves- tigated by ab initio plane-wave pseudopotential density functional theory method. It is found that under the pressure from 0 to 20 GPa the values of c/a ratio keep almost constant 1.02, which is in full agree- ment with the experiment. With the pressure increasing from 20 to 45 GPa the values of c/a ratio decrease almost linearly from 1.02 to 0.99. This indicates under low pressure the compression along caxis and aaxis is the same, but the compression along caxis is easier than along a-axis under higher pressure. The elastic constants of L10-TiA1 have been calculated under different pressures from 0 to 20 GPa. At the same time we have also calculated the shear anisotropy ratio A and Voigt shear modulus G_v, which agree well with the experimental results and other calculated results.