First-principles study on doping effect of B in NbSi2 with C40 structure

doi:10.1016/j.vacuum.2016.11.007

Vacuum

Volume 135, January 2017, Pages 121-123

https://doi.org/10.1016/j.vacuum.2016.11.007 Get rights and content

Highlights

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Solution strengthening mechanism of B in NbSi₂ is studied by first-principles.
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B prefers to occupy to OI site in comparison with the TI site.
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B element results in brittle-to-ductile transition for NbSi₂.
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B element weakens the shear deformation resistance for NbSi₂.

Abstract

The influence of B element on structure and mechanical properties of NbSi₂ is investigated by using the first-principles approach. To explore the solution strengthening mechanism of B element, the doped sites including the octahedral interstice site (OI) and tetrahedral interstice site (TI) are considered. It is found that B element prefers to occupy the OI site in comparison with the TI site. B element occupied OI site can slightly improve the volume deformation resistance for NbSi₂. Importantly, B element leads to brittle-to-ductile transition. The reason is that the addition of B element can weaken the charge interaction between the Nb and Si atoms.

Section snippets

Acknowledgments

This work is supported by National Natural Science Foundation of China (Grant: No.51174171).

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First-principles study on doping effect of B in NbSi2 with C40 structure

Highlights

Abstract

Section snippets

Acknowledgments

Comp. Mater Sci.

Mater Des.

Mater Des.

Scr. Mater

Scr. Mater

Acta Mater

J. Phys. Condens Mat.

First-principles study on doping effect of B in NbSi₂ with C40 structure