Linear relation between surface roughness and work function of light alloys
Linear relation between surface roughness and work function of light alloys
复制标题
轻合金表面粗糙度与功函数的线性关系
DOI：
10.1016/j.jallcom.2016.09.102
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发表时间：
2017
影响因子：
6.2
通讯作者：
Li Wen
中科院分区：
文献类型：
--
作者：
Xue Mingshan;Peng Sibo;Wang Fajun;Ou Junfei;Li Changquan;Li Wen
表面结构与材料性能之间的关系是相当复杂的，如何理解和澄清这种关系对于揭示相关的物理、化学和力学机理具有重要意义。采用扫描开尔文探头和理论分析相结合的方法，研究了表面粗糙度对镁合金和铝合金功函数的影响。随着表面粗糙度的增加，AZ31镁合金和2198铝合金的WF分别从最初的4.3 eV和3.77 eV增加到4.67 eV和3.97 eV。基于最小二乘拟合法和静电场理论，得到了WF与合金表面粗糙度之间的线性关系。由于表面静电场的作用，合金表面越粗糙，粗糙表面附近的静电势越大。相应地，电子的运动和转移被俘获，从表面逃逸的所需能量增加，导致WF随着表面粗糙度的增加而线性增加。
The correlation between surface structures and material properties is rather complicated, and how to understand and clarify the relationship is of much significance for revealing related physical, chemical and mechanical mechanisms. In this study, the effect of surface roughness on the work function (WF) of Mg and Al alloys was investigated by scanning Kelvin probe and theoretical analysis. With the increase of surface roughness, the WF of AZ31 Mg alloy and 2198 Al alloy increased to 4.67 eV and 3.97 eV from initial 4.3 eV and 3.77 eV, respectively. Based on the least-square fitting method and the electrostatic field theory, the linear relationship between the WF and the surface roughness of the alloys was found. Owing to the effect of the surface electrostatic field, the rougher the surface of the alloys was, the larger the electrostatic potential near the rough surface was. Accordingly, the movement and transfer of the electrons were trapped and the required energy escaping from the surface was increased, resulting in the linear increase of the WF with the increase of the surface roughness.