The effect of preload on the pull-off force in indentation tests of microfibre arrays

We determined how preload and work of adhesion control the force required to pull a circular cylindrical indenter off a microfibre array. Five regimes, with different contact behaviours, are identified for the unloading phase of indentation. These regimes are governed by two dimensionless parameters. Above a critical preload, the pull-off force and the pull-off stress reach a plateau value. The critical preload, as well as the plateau pull-off force (stress), is found to depend on a single dimensionless parameter q, which can be interpreted as a normalized work of adhesion.

[1]  Metin Sitti,et al.  Adhesion and anisotropic friction enhancements of angled heterogeneous micro-fiber arrays with spherical and spatula tips , 2007 .

[2]  Anand Jagota,et al.  Mechanics of Adhesion Through a Fibrillar Microstructure1 , 2002, Integrative and comparative biology.

[3]  A. Jagota,et al.  Mechanism of sliding friction on a film-terminated fibrillar interface. , 2009, Langmuir : the ACS journal of surfaces and colloids.

[4]  Lijie Ci,et al.  Gecko-inspired carbon nanotube-based self-cleaning adhesives. , 2008, Nano letters.

[5]  H. Yao,et al.  Adhesion and sliding response of a biologically inspired fibrillar surface: experimental observations , 2008, Journal of The Royal Society Interface.

[6]  A. Majumdar,et al.  Multiwalled Carbon Nanotube/nanofiber Arrays as Conductive and Dry Adhesive Interface Materials , 2004 .

[7]  Huajian Gao,et al.  Mechanical principles of robust and releasable adhesion of gecko , 2007 .

[8]  Metin Sitti,et al.  Adhesion of biologically inspired vertical and angled polymer microfiber arrays. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[9]  Metin Sitti,et al.  Effect of backing layer thickness on adhesion of single-level elastomer fiber arrays , 2007 .

[10]  Ronald S. Fearing,et al.  Synthetic gecko foot-hair micro/nano-structures as dry adhesives , 2003 .

[11]  Chung-Yuen Hui,et al.  Biologically inspired crack trapping for enhanced adhesion , 2007, Proceedings of the National Academy of Sciences.

[12]  S. Gorb,et al.  Biomimetic mushroom-shaped fibrillar adhesive microstructure , 2007, Journal of The Royal Society Interface.

[13]  M. Meyyappan,et al.  Interfacial energy and strength of multiwalled-carbon-nanotube-based dry adhesive , 2006 .

[14]  Stanislav N. Gorb,et al.  The effect of surface roughness on the adhesion of elastic plates with application to biological systems , 2003 .

[15]  Huajian Gao,et al.  Mechanics of robust and releasable adhesion in biology: bottom-up designed hierarchical structures of gecko. , 2006 .

[16]  A. Jagota,et al.  Enhanced adhesion and compliance of film-terminated fibrillar surfaces , 2007, Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences.

[17]  A. Jagota,et al.  Design of bio-inspired fibrillar interfaces for contact and adhesion — theory and experiments , 2007 .

[18]  A. Crosby,et al.  Axisymmetric adhesion tests of soft materials , 1998 .

[19]  Yu Tian,et al.  Adhesion and friction in gecko toe attachment and detachment , 2006, Proceedings of the National Academy of Sciences.

[20]  Kimberly L. Turner,et al.  Meso-scale adhesion testing of integrated micro- and nano-scale structures , 2006 .

[21]  Manoj K. Chaudhury,et al.  Estimation of Adhesion Hysteresis Using Rolling Contact Mechanics , 2000 .

[22]  Bharat Bhushan,et al.  Adhesion of multi-level hierarchical attachment systems in gecko feet , 2007 .

[23]  J. Barbera,et al.  Contact mechanics , 1999 .

[24]  B. Persson,et al.  Biological adhesion for locomotion: basic principles , 2007 .

[25]  Eduard Arzt,et al.  Adhesion of bioinspired micropatterned surfaces: effects of pillar radius, aspect ratio, and preload. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[26]  Metin Sitti,et al.  Biologically inspired polymer microfibers with spatulate tips as repeatable fibrillar adhesives , 2006 .

[27]  S. Gorb,et al.  Spring model of biological attachment pads. , 2006, Journal of theoretical biology.

[28]  Bharat Bhushan,et al.  Adhesion analysis of two-level hierarchical morphology in natural attachment systems for 'smart adhesion' , 2006 .

[29]  Jin Zhai,et al.  Superhydrophobic Aligned Polystyrene Nanotube Films with High Adhesive Force , 2005 .

[30]  Tian Tang,et al.  Can a fibrillar interface be stronger and tougher than a non-fibrillar one? , 2005, Journal of The Royal Society Interface.

[31]  M. Sitti,et al.  Modeling the soft backing layer thickness effect on adhesion of elastic microfiber arrays , 2008 .

[32]  Eduard Arzt,et al.  Contact shape controls adhesion of bioinspired fibrillar surfaces. , 2007, Langmuir : the ACS journal of surfaces and colloids.

[33]  S. Gorb,et al.  WHEN LESS IS MORE: EXPERIMENTAL EVIDENCE FOR TENACITY ENHANCEMENT BY DIVISION OF CONTACT AREA , 2004 .

[34]  K. Kendall,et al.  Surface energy and the contact of elastic solids , 1971, Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences.

[35]  Chung-Yuen Hui,et al.  Adhesive contact of cylindrical lens and a flat sheet , 1996 .