The stiction of a thin plate induced by the capillary force has attracted much attention in the broad range of applications. A novel method is presented to calculate the capillary adhesion problem of the plate through analytical method. The expressions of the surface energy, the strain energy and the total potential energy of the plate-substrate system have been analyzed and delineated. By means of continuum mechanics and the principle of minimum potential energy, the governing equation of the plate with an arbitrary shape and the corresponding transversality boundary condition due to the moving bound have been derived. Then the critical adhesion radius of the circular plate has been solved according to the supplementary transversality condition. Thus the deflections of the plates are analytically calculated with different critical adhesion radii. The results may be beneficial to the engineering application and the micro/nanomeasurement.
The abnormal bending of a micro-cantilever plate induced by a droplet is of great interest and of significance in micro/nano-manipulations. In this study, the physical mechanism of this abnormal phenomenon induced by an actual droplet is elucidated. Firstly, the morphologies of 2D and 3D droplets axe solved analytically or numerically. Then the Laplace pressure difference acting on the cantilever plate caused by the droplet is presented. Finally, the deflections of the micro-cantilever plates driven by the capillary forces are quantitatively analyzed. These analytical results may be beneficial to some engineering applications, such as micro-sensors, MEMS and the micro/nano-measurement.
Jianlin Liu Xueyan Zhu Xinkang Li Zhiwei Li 1(Department of Engineering Mechanics,China University of Petroleum,Qingdao 266555,China)
Elastocapillary phenomena involving elastic deformation of solid structures coupled with capillary effects of liquid droplets/films can be observed in a diversity of fields, e.g., biology and microelectromechanical systems （MEMS）. Understanding the physical mechanisms underlying these phenomena is of great interest for the design of new materials and devices by utilizing the effects of surface tension at micro and nano scales. In this paper, some recent developments in the investigations on elastocapillary phenomena are briefly reviewed. Especially, we consider the deformation, adhesion, self-assembly, buckling and wrinkling of ma- terials and devices induced by surface tensions or capillary forces. The main attention is paid to the experimental results of these phenomena and the theoretical analysis meth- ods based on continuum mechanics. Additionally, the applications of these studies in the fields of MEMS, micro/nanometrology, and biomimetic design of advanced materials and devices are discussed.
