A quasi-dynamic adhesion model is used to calculate the intermolecular adhesion forces present in ultra low flying Head Disk Interfaces (HDI’s). The model is a continuum-based micromechanics model that accounts for realistic surfaces with roughness, molecularly thin lubricants, and is valid under both static and dynamic sliding conditions. Several different levels of surface roughness are investigated ranging from extremely smooth surfaces having a standard deviation of surface heights σ=2 Å to rougher interfaces with several nanometer roughness. It is found that when the flying-height is greater than 5 nm, there are no significant adhesive forces, whereas for flying-heights less than 5 nm, adhesion forces increase sharply, which can be catastrophic to the reliability of low flying HDI’s. In addition to roughness, the apparent area of contact between the flying recording slider and the magnetic disk is also found to significantly affect the magnitude of the adhesion forces. The adhesion model is validated by direct comparisons with adhesion “pull-off” force measurements performed using an Atomic Force Microscope with controlled probe tip areas and magnetic disks having different lubricant thickness.
Issue Section:
Technical Papers
1.
Wood
, R. W.
, Miles
, J.
, and Olson
, T.
, 2002
, “Recording Technologies for Terabit per Square Inch Systems
,” IEEE Trans. Magn.
, 38
(4
), pp. 1711
–1718
.2.
Wang
, R. H.
, Nayak
, V.
, Huang
, F. Y.
, Tang
, W.
, and Lee
, F.
, 2001
, “Head-Disk Dynamics in the Flying, Near Contact, and Contact Regimes
,” ASME J. Tribol.
, 123
, pp. 561
–565
.3.
O’Hara
, M. A.
, Hu
, Y.
, and Bogy
, D. B.
, 2000
, “Optimization of Proximity Recording Air Bearing Sliders in Magnetic Hard Disk Drive
,” ASME J. Tribol.
, 122
, pp. 257
–259
.4.
Knigge, B., and Talke, F. E., 2000, “Contact Force Measurement Using Acoustic Emission Analysis and System Identification Methods,” Tribology International, 33(9), pp. 639–646.
5.
Guruz, M. U., Dravid, V. P., Chung, Y. W., Lacerda, M. M., Bahtia, C. S., Yu, Y. H., and Lee, S. C., 2001, “Synthesis and Corrosion Performance of Ultrathin Carbon Nitride Overcoats,” Thin Solid Films, 381, pp. 6–9.
6.
Chen
, C. Y.
, and Bogy
, D. B.
, 2001
, “Effects of Backbone and Endgroup on the Decomposition Mechanisms of PFPE Lubricants and Their Tribological Performance at the Head-Disk Interface
,” ASME J. Tribol.
, 123
, pp. 364
–367
.7.
Mate
, C. M.
, Kasai
, P. H.
, Tyndall
, G. W.
, Lee
, C. H.
, Raman
, V.
, Pocker
, D. J.
, and Waltman
, R. J.
, 1998
, “Investigation of Phosphazene Additive for Magnetic Recording Lubrication
,” IEEE Trans. Magn.
, 34
(4
), pp. 1744
–1746
.8.
Israelachvili, J. N., 1991, Intermolecular and Surface Forces, 2nd ed., Academic Press, San Diego.
9.
Polycarpou, A. A., 2000, “Surface Topography Characterization and Adhesion Modeling of 100 Gbit/in2 Samples,” presented at the Extremely High Density Recording (EHDR) annual meeting, National Storage Industry Consortium (NSIC), June 26–29, 2000, CA.
10.
Polycarpou, A. A., 2003, “Modeling Adhesive Forces for Ultra Low Flying Head Disk Interfaces,” in Nanotribology: Critical Assessment and Research Needs, S. M. Hsu, and Z. C. Ying, eds., Kluwer Academic Publishers.
11.
Wu
, L.
, and Bogy
, D. B.
, 2002
, “Effects of the Intermolecular Forces on the Flying Attitude of Sub-5 nm Flying Height Air Bearing Sliders in Hard Disk Drives
,” ASME J. Tribol.
, 124
, pp. 562
–567
.12.
Hanchi, J., Polycarpou, A. A., and Boutaghou, Z., 1999, “Tribology of Contacting Head-Disk Interface,” Proceedings of the Symposium on Interface Technology Towards 100 Gbit/in2, TRIB-Vol. 9, pp. 17–22.
13.
Polycarpou
, A. A.
, and Etsion
, I.
, 1998
, “Static Friction of Contacting Real Surfaces in the Presence of Sub-Boundary Lubrication
,” ASME J. Tribol.
, 120
, pp. 296
–303
.14.
Wang, R. H., Raman, V., and Nayak, U. V., 2001, “Head-Disk Interface Issues for Near Contact Recording,” Proceedings of the Symposium on Interface Technology Towards 1 Tbit/in2, TRIB-Vol. 11, pp. 37–2.
15.
Derjaguin
, B. V.
, Muller
, V. M.
, and Toporov
, Y. P.
, 1975
, “Effect of Contact Deformations on the Adhesion of Particles
,” J. Colloid Interface Sci.
, 53
, pp. 314
–326
.16.
Johnson
, K. L.
, Kendall
, K.
, and Roberts
, A. D.
, 1971
, “Surface Energy and the Contact of Elastic Solids
,” Proc. R. Soc. London, Ser. A
, 324
, pp. 301
–313
.17.
Greenwood
, J. A.
, and Williamson
, J. B. P.
, 1966
, “Contact of Nominally Flat Surfaces
,” Proc. R. Soc. London, Ser. A
, 295
, pp. 300
–319
.18.
Majumdar
, A.
, and Bhushan
, B.
, 1991
, “Fractal Model of Elastic-Plastic Contact Between Rough Surfaces
,” ASME J. Tribol.
, 113
, pp. 1
–11
.19.
Muller
, V. M.
, Derjaguin
, B. V.
, and Toporov
, Y. P.
, 1983
, “On Two Methods of Calculation of the Forces of Sticking of an Elastic Sphere to a Rigid Plane
,” Colloids Surf.
, 7
, pp. 251
–259
.20.
Chang
, W. R.
, Etsion
, I.
, and Bogy
, D. B.
, 1987
, “An Elastic-Plastic Model for the Contact of Rough Surfaces
,” ASME J. Tribol.
, 109
, pp. 257
–263
.21.
Chang
, W. R.
, Etsion
, I.
, and Bogy
, D. B.
, 1988
, “Adhesion Model for Metallic Rough Surfaces
,” ASME J. Tribol.
, 110
, pp. 50
–56
.22.
Stanley
, H. M.
, Etsion
, I.
, and Bogy
, D. B.
, 1990
, “Adhesion of Contacting Rough Surfaces in the Presence of Sub-Boundary Lubrication
,” ASME J. Tribol.
, 112
, pp. 98
–104
.23.
Polycarpou
, A. A.
, and Etsion
, I.
, 1998
, “Comparison of the Static Friction Subboundary Lubrication Model With Experimental Measurements on Thin Film Disks
,” STLE Tribol. Trans.
, 41
, pp. 217
–224
.24.
Gui
, J.
, and Marchon
, B.
, 1995
, “A Stiction Model for a Head-Disk Interface of a Rigid Disk Drive
,” J. Appl. Phys.
, 78
(6
), pp. 4206
–4217
.25.
Gui
, J.
, and Marchon
, B.
, 1998
, “Fly/Stiction: Mechanical Instability of a Head-Disk Interface
,” IEEE Trans. Magn.
, 34
, pp. 1804
–1806
.26.
Kral
, E. R.
, Komvopoulos
, K.
, and Bogy
, D. B.
, 1996
, “Hardness of Thin-Film Media: Scratch Experiments and Finite Element Simulations
,” ASME J. Tribol.
, 118
, pp. 1
–11
.27.
Bhushan, B., 1990, Tribology and Mechanics of Magnetic Storage Devices, Springer-Verlag, New York, pp. 604–605.
28.
McCool
, J. I.
, 1987
, “Relating Profile Instrument Measurements of the Functional Performance of Rough Surfaces
,” ASME J. Tribol.
, 109
, pp. 264
–279
.29.
Thornton
, B. H.
, Nayak
, A.
, and Bogy
, D. B.
, 2002
, “Flying Height Modulation due to Disk Waviness of Sub-5 nm Flying Height Air Bearing Sliders
,” ASME J. Tribol.
, 124
, pp. 762
–770
.30.
Ando
, Y.
, 2000
, “Wear Tests and Pull-Off Force Measurements of Single Asperities by Using Parallel Leaf Springs Installed on an Atomic Force Microscope
,” ASME J. Tribol.
, 122
, pp. 639
–645
.Copyright © 2004
by ASME
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