Gravity-induced wrinkling of thin films on soft substrates
1 School of Civil Engineering, Anhui University of Architecture - Hefei, Anhui 230601, PRC
2 Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093, USA
Received: 10 September 2012
Accepted: 19 November 2012
In this letter, we investigate the wrinkling instability of a stiff thin film bonded on a soft substrate, induced by the gravity of densely packed pillars adhered on the surface of the film. By using linear perturbation analysis, we show that the gravity of the pillars can induce wrinkling instability of the system when the gravitational force of the pillars is large enough. Our calculation results give the instability criterion and illustrate how the wavelength of the wrinkles varies with several parameters of the system. The results of this article may be useful in the applications of similar pillar structures.
PACS: 46.32.+x – Static buckling and instability / 68.55.J- – Morphology of films
© EPLA, 2012