DOI QR코드

DOI QR Code

Analysis of Surface Forces in Micro Contacts between Rough Surfaces

거친 표면간의 미세 접촉에서의 표면력 해석

  • 김두인 (한양대학교 대학원 기계설계학과/한국과학기술) ;
  • 안효석 (한국과학기술연구원 트라이볼로지연구센터) ;
  • 최동훈 (한양대학교 기계공학부)
  • Published : 2002.10.01

Abstract

In a micro-scale contact, capillary force and van der Waals interaction significantly influence the contact between asperities of rough surfaces. Little is, however, known about the variation of these surface forces as a function of chemical property of the surface (wet angle), relative humidity and deformation of asperities in the real area of contact. A better understanding of these surface forces is of great necessity in order to find a solution for reducing friction and adhesion of micro surfaces. The objective of this study is to investigate the surface forces in micro-scale rough surface contact. We proposed an effective method to analyze capillary and van der Waals forces in micro-scale contact. In this method, Winkler spring model was employed to analyze the contact of rough surfaces that were obtained from atomic force microscopy (AFM) height images. Self-mated contact of DLC(diamond like carbon) coatings was analyzed, as an example, by the proposed model. It was shown that the capillary force was significantly influenced by relative humidity and wet angle of the DLC surface. The deformation of asperities to a critical magnitude by external loading led to a considerable increase of both capillary and van der Waals forces.

Keywords

Rough Surface;Micro Contact;Van Der Waals force;Capillary Force;Surface Energy

References

  1. Kim, D. -I. and Ahn, H. -S., 2002, 'Etching Voltage Control Technique for Electrochemical Fabrication of Scanning Probe Microscope Tips,' Rev. Sci. Instrum., Vol. 73, No.3, pp. 1337-1339 https://doi.org/10.1063/1.1384424
  2. Israelachvili, J. N., 1991, Intermolecular and Surface Forces, 2nd ed. Academic press, London
  3. Johnson, K. L., 1985, Contact Mechanics, Cambridge University Press
  4. Tian, X. and Bhushan, B., 1996, 'A Numerical Three-Dimensional Model for the Contact of Rough Surfaces by Variational Principle,' ASME J. of Tribology, Vol. 118, pp. 33-42 https://doi.org/10.1115/1.2837089
  5. Chizhik, S. A., Gorbunov, V. V. and Myshkin, N. K., 1995, 'Analysis of Molecular Scale Roughness Effect on Contact of Solids based on Computer Modeling,' Precision Engineering, Vol. 17, pp. 186-191 https://doi.org/10.1016/0141-6359(94)00016-S
  6. Tian, H. and Matsudaire, T., 1993, 'The Role of Relative Humidity, Surface Roughness and Liquid Build-up on Static Friction Behavior of the Head/Disk Interface,' ASME J. of Tribology, Vol. 115, pp. 28-35 https://doi.org/10.1115/1.2920983
  7. Adamson, A. W., 1990, Physical Chemistry of surfaces, 5th ed. Wiley
  8. Maugis, D., 1992, 'Adhesion of Spheres: The JKRDMT Transition using a Dugdale Model,' J. of Colloid and Interface Science, Vol. 150, pp. 243-268 https://doi.org/10.1016/0021-9797(92)90285-T
  9. Greenwood, J. A. and Williamson, J. B. P., 1966, 'Contact of Nominally Flat Surfaces,' Proc. Roy. Soc. A, Vol. 295, pp. 300-329 https://doi.org/10.1098/rspa.1966.0242
  10. Whitehouse, D. J. and Archard, J. F., 1970, 'The Properties or Random Surfaces of Significance in Their Contact,' Proc. Roy. Soc. A, Vol.316, pp. 97-121 https://doi.org/10.1098/rspa.1970.0068
  11. Lee, S. C. and Cheng, H. S., 1992, 'On the Relation of Load to Average Gap in the Contact between Surfaces with Longitudinal Roughness,' STLE Tribology Trans., Vol. 35, pp. 523-529 https://doi.org/10.1080/10402009208982151
  12. Johnson, K. L., Kendall, K. and Roberts, A.D., 1971, 'Surface Energy and the Contact of Elastic Solids,' Proc. R. Soc. Lond. A, Vol. 324, pp. 301-313 https://doi.org/10.1098/rspa.1971.0141
  13. Derjaguin, B.Y., Muller, V. M. and Toporov, Y. P., 1975, 'Effect of Contact Deformations on the Adhesion of Particles,' J. of Colloid and Interface Science, Vol. 53, pp. 314-326 https://doi.org/10.1016/0021-9797(75)90018-1
  14. Muller, V. M., Yushchenko, Y. S. and Derjaguin, B. V. 1980, 'On the Influence of Molecular Forces on the Deformation of an Elastic Sphere and its Sticking to a Rigid Plane,' J. of Colloid an Interface Science, Vol. 77,pp.91-101 https://doi.org/10.1016/0021-9797(80)90419-1
  15. Komvopoulos, K., 1996, 'Surface engineering and Microtribology for Microelectro Mechanical System,' Wear, Vol.200,pp. 305-327 https://doi.org/10.1016/S0043-1648(96)07328-0
  16. Miller,S. L., Rodgers, M. S., Vigne, G. La, Sniegowski, J.J., Clews, P., Tanner, D. M. and Peterson, K. A., 1999, 'Failure Modes in Surface Micromachined Micro- Eletromechanical Actuation System,' Microelectronics Reliability, Vol. 39, pp. 1229-1237 https://doi.org/10.1016/S0026-2714(99)00013-X
  17. Maboudian, R. and Howe, R. T., 1997, 'Critical Review: Adhesion in Surface Micromechanical Structure,' J. Vac. Sci. Technol. B, Vol. 15, pp. 1-20 https://doi.org/10.1116/1.589247
  18. Tanner, D. M. 2000, 'Reliability of Surface Micromachined Microelectromechanical Actuators,' 22nd Int. Conf. In Microelectronics, pp. 97-104 https://doi.org/10.1109/ICMEL.2000.840535
  19. Hornbeck, L. J. 1996, 'Digital Light Processing! and MEMS: Reflecting the Digital Display Needs of the Networked Society,' Proc. of SPIE, Vol. 2783, pp. 2-13 https://doi.org/10.1117/12.248477