Buckling of an Adhesive Polymeric Micropillar

作者：Paretkar Dadhichi R; Bartlett Michael D; McMeeking Robert; Cro**y Alfred J; Arzt Eduard^*

来源：The Journal of Adhesion, 2013, 89(2): 140-158.

DOI：10.1080/00218464.2013.731941

• Aspect ratio
• Fibril buckling
• Gecko adhesion
• Reversible adhesion
• Single fibirl
• Tip shape

Adhesion and buckling of single PDMS micropillars were investigated as a function of compressive preload. The micropillars had diameters of 10, 12, 14, and 20 mu m and aspect ratios of 1 to 3.3. Adhesion generally increased with a decrease in the aspect ratio. A dependence of pull-off strength on the compressive preload stress was found for micropillars that underwent buckling. When buckling was reversible, tip contact recovered upon unbuckling, which resulted in only a slight reduction of adhesion. In situ observation studies identified irreversible buckling, i.e., lack of tip-contact re-formation, resulting in adhesion loss. It is concluded that the edge radius of the tip, which acts as a circumferential crack, controls adhesion. Fibril buckling is found to be broadly consistent with the predictions of Euler buckling theory.

• 出版日期2013