Atomic-scale segregation behavior of Sn/Ti and O at Sigma 3[1(1)over-bar0](111) grain boundary in niobium

作者：Liu, Zenghui; Shang, Jiaxiang^*

来源：Progress in Natural Science:Materials International , 2016, 26(2): 152-157.

DOI：10.1016/j.pnsc.2016.03.012

• Grain bounday segregation
• First-principles
• Niobium alloys
• Alloying elements

First-principle calculation was performed to illustrate the atomic arrangement and segregation behavior of Sn/Ti and O in Sigma 3[1 (1) over bar0](111) grain boundary, and the interaction of oxygen interstitials with Sn/Ti atoms on the grain boundary was studied. The analyses on the segregation energies and geometric positions, and the electron densities show that Sn, Ti and O atoms segregate at the Sigma 3 grain boundary. And the preferred segregation sites of the impurities at Sigma 3[1 (1) over bar0](111) were determined. When Sn segregates at grain boundary plane, the O atom prefers to the bulk-like site and shows no segregation tendency at grain boundary, whereas the segregated Ti atom can slightly enhance oxygen segregation at the grain boundary.

• 出版日期2016-4
• 单位北京航空航天大学