带有尖角基体上异质形核能力的研究

Ability of Heterogeneous Nucleation in Substrate with Sharp Corners

目的基体表面分别为平面、圆柱面和椭圆柱面时,研究带有尖角基体上的异质形核的难易程度。方法基于经典形核理论,应用热力学理论方法,分析形核基体的几何特征和材料属性对临界形核功的影响规律,并对其形核能力进行比较。结论当润湿角为锐角时,基体形核能力均随着尖角的增大而减小,在带尖角平面基体上最容易形核;当润湿角为钝角时,随着尖角的增大,基体形核能力都是先增加后减小,相互之间形核能力的关系与几何特征相关。特别地,在具有特殊几何特征的带尖角椭圆柱面基体上会发生二次形核。

This paper aims to study the problem of heterogeneous nucleation in the substrate with sharp corners, and discuss the difficulty of nucleation when the surface of the substrate is a planar, a cylinder and an elliptical cylinder. Based on the classical nucleation theory and the thermodynamic method, effects of the geometrical characteristics and the material properties of the nucleation substrate on the critical nucleation work were analyzed and compared. Results show that when the wetting angle was acute, the nucleation ability of the substrate decreased with the increase of the sharp corners, and the nucleation was the easiest in the planar substrate; when the wetting angle was obtuse, with the increase of sharp corners, the substrate nucleation ability increased first and then decreased. The relationship between the nucleation ability of each other was related to geometric characteristics. In particular, in a certain range of wetting angle and sharp corners, secondary nucleation would occur on the elliptical cylinder substrate with sharp corners.