CAJ | 학술논문

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-TiA1金属间化合物的结构和弹性性质.研究发现当压力在0～20 GPa范围内时,c/a的值基本上保持一常数1.02,与实验结果吻合.当压力在20～45 GPa范围内时,c/a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c轴和沿a轴的压缩性是一样的,但是高压下沿c轴比沿a轴更容易压缩.计算了从O到20 GPa压力下L10-TiA1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.
이용종두산평면파안세밀도범함이론방법연구료고압하L10-TiA1금속간화합물적결구화탄성성질.연구발현당압력재0～20 GPa범위내시,c/a적치기본상보지일상수1.02,여실험결과문합.당압력재20～45 GPa범위내시,c/a적치수압력적증가종1.02선성감소도0.99.저표명재저압하연c축화연a축적압축성시일양적,단시고압하연c축비연a축경용역압축.계산료종O도20 GPa압력하L10-TiA1적탄성상수.동시아문환계산료전절각향이성비솔A화Voigt전절모량,여실험결과화별인적계산결과상문합.
The structural and elastic properties of L10-TiA1 intermetallics under high pressure are investigated 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 agreement 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 c-axis and a-axis is the same,but the compression along c-axis is easier than along a-axis under higher pressure.The elastic constants of L10-TiAl 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 Gv,which agree well with the experimental results and other calculated results.