Role of impurities in the formation of point defects in Ti-Al alloys

被引：0

作者：

Bakulin, A. V. ^{[1
,2
]}

Fuks, A. A. ^{[1
]}

Kulkova, S. E. ^{[1
,2
]}

机构：

[1] Natl Res Tomsk State Univ, Pr Lenina 36, Tomsk 634050, Russia

[2] Russian Acad Sci, Siberian Branch, Inst Strength Phys & Mat Sci, Pr Akad Sky 2-4, Tomsk 634055, Russia

来源：

FUNCTIONAL MATERIALS AND NANOTECHNOLOGIES (FM&NT 2018) | 2019年 / 503卷

基金：

俄罗斯基础研究基金会;

关键词：

TI3AL;

D O I：

10.1088/1757-899X/503/1/012003

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The effect of impurities on the point defect formation energies in Ti-Al alloys was studied by the projector augmented-wave method. The grand canonical formalism was applied to calculate the formation energies of several kinds of defects. It was shown that the formation energy of Al-vacancy decreases by similar to 1.3 eV with increasing its content in the series of alloys Ti3Al-TiAl-TiAl3, whereas the formation energy of Ti-vacancy changes insignificantly. In general, the formation of Ti-vacancies is more preferred in Ti-Al alloys rather than the formation of Al-vacancies. We demonstrate that Nb, Mo, Tc, Ru, Rh, Pd lead to increase of the formation energy of Al-vacancy if they occupy the Al sites, whereas only Mo and Tc increase the formation energy of Ti-vacancy. All 4d elements, if they substitute for Ti, reduce the formation energies of Al-vacancy. The influence of impurities on elastic constants is discussed.

引用

页数：4

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