Intermolecular force and surface roughness models for air bearing simulations for sub-5 nm flying height sliders

  • Du ChenEmail author
  • David B. Bogy
Technical Paper


When the spacing between the slider and the disk is less than 5 nm, the intermolecular forces between the two solid surfaces can no longer be assumed to be zero. The model proposed by Wu and Bogy (ASME J Trib 124:562–567, 2002) can be view as a flat slider–disk intermolecular force model. The contact distance between the slider and disk needs to be considered in this model when the slider-disk spacing is in the contact regime. To get more accurate intermolecular force effects on the head disk interface, the slider and disk surface roughness need to be considered, when the flying height is comparable to the surface RMS roughness value or when contact occurs. With the intermolecular force model and asperity model implemented in the CML air bearing program, the effect of intermolecular adhesion stress on the slider at low flying height is analyzed in the static flying simulation. It is found that the intermolecular adhesion stress between the slider and the disk has slight effect on the slider-disk interface for a flying slider.


Asperity Contact Flying Height Disk Interface Head Disk Interface Adhesion Stress 
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This research was supported by the Information Storage Industry Consortium (INSIC), the Computer Mechanics Laboratory (CML) at the University of California at Berkeley, and the National Science Foundation under Grant CMS-0408484.


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Computer Mechanics Laboratory, Department of Mechanical EngineeringUniversity of California at BerkeleyBerkeleyUSA

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