Microsystem Technologies

, Volume 21, Issue 7, pp 1501–1511

Optimization of molecularly thin lubricant to improve bearing capacity at the head-disk interface

  • Shahla Chowdhury
  • Antonis I. Vakis
  • Andreas A. Polycarpou
Technical Paper

Abstract

A molecularly thin lubricant layer (of the order of 1–2 nm thick) has been shown to provide bearing forces at the interface between contacting solid surfaces under light loads and high shear rates. This phenomenon is important, for example, in the head-disk contact in magnetic storage hard disk drives to ensure that some of the contact is sustained by the lubricant layer and thus avoiding damage of the solid surfaces. The magnitude of the normal and tangential bearing forces that the lubricant layer can provide depends on temperature, viscosity of the lubricant, sliding velocity and radius of gyration of the lubricant molecules. This study shows that viscosity has the greatest effect on the load bearing capacity of the molecularly thin lubricant. Thus, by controlling the flash temperature and the ratio of molecularly thin lubricant-to-bulk viscosity, the bearing load carrying capacity of the layer can be controlled. This would allow for the contact to be sustained within the mobile lubricant layer, avoiding solid contact so as to protect the diamond-like carbon coating, and thus reduce wear and potential catastrophic failures.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Shahla Chowdhury
    • 1
    • 2
  • Antonis I. Vakis
    • 1
    • 3
  • Andreas A. Polycarpou
    • 1
    • 2
  1. 1.Department of Mechanical Science and EngineeringUniversity of Illinois at Urbana-ChampaignChampaignUSA
  2. 2.Department of Mechanical EngineeringTexas A&M UniversityCollege StationUSA
  3. 3.Faculty of Mathematics and Natural SciencesUniversity of GroningenGroningenThe Netherlands

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