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

Abstract

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

lTAS

Length of the thermal asperity sensor

wTAS

Width of the thermal asperity sensor

tTAS

Thickness of the thermal asperity sensor

RTA/tTAS

Normalized cap radius of the asperity

dTA/tTAS

Normalized cylinder diameter of the asperity

hTA/tTAS

Normalized asperity height

RTP/tTAS

Normalized radius of the thermal protrusion on the slider

δ/tTAS

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

D/tTAS

Normalized distance of asperity to thermal asperity sensor

Vx/V0

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

TR

Room temperature

T1/TR

Normalized initial temperature of Al2O3 #1 slider region

T2/TR

Normalized initial temperature of Al2O3 #2 slider region

TTAS/TR

Normalized operational temperature of the thermal asperity sensor

T/TR

Normalized temperature of the thermal asperity sensor

t/t0

Normalized total contact time, where t0 = 1 μs

Tb

Bulk temperature

μ

Frictional coefficient

F

Normal force acting on sliding surfaces

Ar

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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