Surface segregation of the metal impurity to the (100) surface of fcc metals

Pramana

Ke-Wei Xu¹  Bo Wang²  Jian-Min Zhang1² 

[1] State-Key Laboratory for Mechanical Behavior of Materials, Xian Jiaotong University, Xian 710049, Shaanxi, People’s Republic China$$;College of Physics and Information Technology, Shaanxi Normal University, Xian 710062, Shaanxi, People’s Republic of China$$

关键词: Fcc metals;    surface segregation;    modified analytic embedded-atom method and surface energy.;   

DOI  :  

学科分类：物理（综合）

来源: Indian Academy of Sciences

【 摘 要 】

The surface segregation energies for a single metal impurity to the (100) surface of nine fcc metals (Cu, Ag, Au, Ni, Pd, Pt, Rh, Al and Ir) have been calculated using the MAEAM and molecular dynamics (MD) simulation. The results show that the effect of the surface is down to the fourth-layer and an oscillatory or monotonic damping (|𝐸1| > |𝐸2| > |𝐸3| > |𝐸4|) phenomenon in segregation energy has been obtained. The absolute value of the segregation energy 𝐸1 for a single impurity in the first atomic layer is much higher than that in the nether layers. Thus, whether the surface segregation will work or not is mainly determined by 𝐸1 which is in good relation to the differences in surface energy between the impurity and host crystals 𝛥 𝑄 = 𝑄imp - 𝑄hos. So we conclude that an impurity with lower surface energy will segregate to the surface of the host with higher surface energy.

【 授权许可】

Unknown