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Adhesion and Friction Forces of Micro Surface Bumps

  • 조성산 (홍익대학교 기계 시스템디자인공학과) ;
  • 임제성 (홍익대학교 대학원) ;
  • 박승호 (홍익대학교 기계 시스템디자인공학과) ;
  • 이승섭 (한국과학기술원 기계공학과)
  • 발행 : 2004.08.01


Adhesion and friction forces influence adversely on performance and durability of MEMS. It has been reported that the adhesion and friction forces can be reduced with the introduction of micro surface bumps into the contacting interfaces. In this study experiments were conducted to investigate comparatively the effect of hemispherical and torus micro bumps on the adhesion and friction forces. It is confirmed that micro bumps reduce the adhesion and friction forces, and their effect is more pronounced with the bumps of smaller outer boundary radius. Moreover, the results shows that the torus bumps exhibit more rapid decrease of the adhesion and friction forces with the decrease in the outer boundary radius of bump than the hemispherical bumps. When the magnitude of adhesion force is same, the torus bumps generate smaller friction force than the hemispherical bumps. The usage of hemispherical and torus bumps to reduce the adhesion and friction forces in MEMS is discussed.


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