Microsystem Technologies

, Volume 20, Issue 8–9, pp 1529–1534

An investigation of thermal asperity sensors during contact with disk asperities

  • Chuanwei Zhang
  • Andrey Ovcharenko
  • Min Yang
  • Neil Knudson
  • Frank E. Talke
Technical Paper


In this study, a thermo-mechanical finite element model was developed for the response of a thermal asperity sensor sliding against a disk asperity. The temperature change of the thermal asperity sensor due to frictional heating was determined. The effect of disk asperity material properties and contact conditions is investigated.

List of symbols


Length of the thermal asperity sensor


Width of the thermal asperity sensor


Thickness of the thermal asperity sensor


Normalized cap radius of the asperity


Normalized cylinder diameter of the asperity


Normalized asperity height


Normalized radius of the thermal protrusion on the slider


Normalized interference between the thermal protrusion of the slider and the disk asperity


Normalized distance of asperity to thermal asperity sensor


Normalized circumferential velocity of the disk, where V0 is 20 m/s


Room temperature


Normalized initial temperature of Al2O3 #1 slider region


Normalized initial temperature of Al2O3 #2 slider region


Normalized operational temperature of the thermal asperity sensor


Normalized temperature of the thermal asperity sensor


Normalized total contact time, where t0 = 1 μs


Bulk temperature


Frictional coefficient


Normal force acting on sliding surfaces


Actual contact area

k1, k2

Thermal conductivities of surfaces 1 and 2

l1f, l2f

Equivalent linear heat-diffusion distances for surfaces 1 and 2


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Copyright information

© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  • Chuanwei Zhang
    • 1
    • 3
  • Andrey Ovcharenko
    • 2
  • Min Yang
    • 2
  • Neil Knudson
    • 2
  • Frank E. Talke
    • 3
  1. 1.School of Mechatronics EngineeringHarbin Institute of TechnologyHarbinPeople’s Republic of China
  2. 2.Western Digital CorporationSan JoseUSA
  3. 3.Center for Magnetic Recording ResearchUniversity of CaliforniaSan DiegoUSA

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