Scratch-related magnetic signal degradation can occur during magnetic storage hard disk drive operations when the read-write heads contact the spinning multilayer disks. To investigate this phenomenon, controlled nanoscratch experiments were performed on perpendicular magnetic recording media using various indenters of different radii of curvature. Various loading conditions were used to cause permanent scratches that were measured using atomic force microscopy. The nanoscratch experiments were simulated using finite element analysis (FEA) that included the detailed nanometer scale thin-film multilayer mechanical properties. The permanently deformed field in the subsurface magnetic recording layer was extracted from the FEA results. The residual scratch widths measured on the surface of the magnetic storage disk were directly compared with the residual subsurface widths of the region on the magnetic recording layer, where extensive permanent lateral deformation was present. It was found that the subsurface widths of the deformed regions were significantly larger than the surface scratch widths. Thus, subsurface thin-film layers, such as the magnetic recording layer, could be damaged without observable damage to the protective top surface carbon overcoat. The exact location and extent of damage to the magnetic recording layer depends on the scratch load, size of scratch tip, and the friction at the interface. Such permanent deformation in magnetic recording layer could lead to demagnetization, which has been reported in the literature.
Issue Section:
Magnetic Storage
Keywords:
atomic force microscopy,
deformation,
demagnetisation,
finite element analysis,
friction,
hard discs,
magnetic multilayers,
magnetic storage,
magnetic thin film devices,
nanoindentation,
perpendicular magnetic recording,
magnetic storage,
nanoscratch,
finite element analysis,
demagnetization,
multilayer thin-films
1.
Lee
, S. -C.
, Hong
, S. -Y.
, Kim
, N. -Y.
, Ferber
, J.
, Che
, X.
, and Strom
, B. D.
, 2009, “Stress Induced Permanent Magnetic Signal Degradation of Perpendicular Magnetic Recording System
,” ASME J. Tribol.
0742-4787, 131
(1
), p. 011904
.2.
Furukawa
, M.
, Xu
, J.
, Shimizu
, Y.
, and Kato
, Y.
, 2008, “Scratch Induced Demagnetization of Perpendicular Magnetic Disk
,” IEEE Trans. Magn.
0018-9464, 44
(11
), pp. 3633
–3636
.3.
Xu
, J.
, Furukawa
, M.
, Nakamura
, J.
, and Honda
, M.
, 2009, “Mechanical Demagnetization at Head Disk Interface of Perpendicular Recording
,” IEEE Trans. Magn.
0018-9464, 45
(2
), pp. 893
–898
.4.
Jeong
, T. G.
, and Bogy
, D. B.
, 1993, “Dynamic Loading Impact Induced Demagnetization in Thin Film Media
,” IEEE Trans. Magn.
0018-9464, 29
(6
), pp. 3903
–3905
.5.
Liu
, B.
, and Ma
, Y.
, 2003, “Visualization and Characterization of Slider-Disk Interactions in Dynamic Load/Unload Processes
,” IEEE Trans. Magn.
0018-9464, 39
(2
), pp. 743
–748
.6.
Knigge
, B.
, and Talke
, F. E.
, 2000, “Contact Force Measurement Using Acoustic Emission Analysis and System Identification Methods
,” Tribol. Int.
0301-679X, 33
(9
), pp. 639
–646
.7.
Suk
, M.
, and Gillis
, D.
, 1998, “Effect of Slider Burnish on Disk Damage During Dynamic Load/Unload
,” ASME J. Tribol.
0742-4787, 120
(2
), pp. 332
–338
.8.
Fu
, T. -C.
, and Bogy
, D. B.
, 2000, “Analysis of Stresses Induced by Dynamic Load Head-Disk Contacts
,” ASME J. Tribol.
0742-4787, 122
(1
), pp. 233
–237
.9.
Yu
, N.
, Polycarpou
, A. A.
, and Hanchi
, J. V.
, 2008, “Elastic Contact Mechanics-Based Contact and Flash Temperature Analysis of Impact-Induced Head Disk Interface Damage
,” Microsyst. Technol.
0946-7076, 14
(2
), pp. 215
–227
.10.
Katta
, R. R.
, Polycarpou
, A. A.
, Hanchi
, J. V.
, and Roy
, M.
, 2009, “Analytical and Experimental Elastic-Plastic Impact Analysis of Magnetic Storage Head-Disk Interfaces
,” ASME J. Tribol.
0742-4787, 131
(1
), p. 011902
.11.
Katta
, R. R.
, Polycarpou
, A. A.
, Hanchi
, J. V.
, and Crone
, R. M.
, 2009, “High Velocity Oblique Impact and Coefficient of Restitution of Head-Disk Interface Operational Shock
,” ASME J. Tribol.
0742-4787, 131
(2
), p. 021903
.12.
Hoshi
, Y.
, Matsuoka
, M.
, Naoe
, M.
, and Yamanaka
, S.
, 1984, “Demagnetization of Co-Cr Films Induced by Stress and Heat
,” IEEE Trans. Magn.
0018-9464, 20
(5
), pp. 797
–799
.13.
Chikazumi
, S.
, 1964, Physics of Magnetism
, Wiley
, New York
.14.
Lin
, J. K.
, Sivertsen
, J. M.
, and Judy
, J. H.
, 1986, “Origins of Stress-Induced Perpendicular Magnetic Anisotropy of Sputtered Iron Oxide Thin Films
,” IEEE Trans. Magn.
0018-9464, 22
(5
), pp. 594
–596
.15.
Mauri
, D.
, Speriosu
, V. S.
, Yogi
, T.
, Castillo
, G.
, and Peterson
, D. T.
, 1990, “Magnetoelastic Properties of Very Thin Co-Alloy Films
,” IEEE Trans. Magn.
0018-9464, 26
(5
), pp. 1584
–1586
.16.
King
, R. B.
, and O’Sullivan
, T. C.
, 1987, “Sliding Contact Stresses in a Two-Dimensional Layered Elastic Half-space
,” Int. J. Solids Struct.
0020-7683, 23
(5
), pp. 581
–597
.17.
Tian
, H.
, and Saka
, N.
, 1991, “Finite Element Analysis of an Elastic-Plastic Two Layer Half Space: Normal Contact
,” Wear
0043-1648, 148
(1
), pp. 47
–68
.18.
Tian
, H.
, and Saka
, N.
, 1991, “Finite Element Analysis of an Elastic-Plastic Two Layer Half Space: Sliding Contact
,” Wear
0043-1648, 148
(2
), pp. 261
–285
.19.
Kral
, E. R.
, and Komvpoulos
, K.
, 1996, “Three-Dimensional Finite Element Analysis of Subsurface Stresses and Shakedown Due to Repeated Sliding on a Layered Medium
,” ASME J. Appl. Mech.
0021-8936, 63
(4
), pp. 967
–973
.20.
Katta
, R. R.
, Escobar
, E. N.
, Polycarpou
, A. A.
, and Lee
, S. -C.
, 2009, “Plane Strain Sliding Contact of Multilayer Magnetic Storage Thin-Films Using the Finite Element Method
,” Microsyst. Technol.
0946-7076, 15
(7
), pp. 1097
–1110
.21.
Holmberg
, K.
, Laukkanen
, A.
, Ronkainen
, H.
, Walin
, J.
, and Varjus
, S.
, 2003, “A Model for Stresses, Crack Generation and Fracture Toughness Calculation in Scratched TiN-Coated Steel Surfaces
,” Wear
0043-1648, 254
(3–4
), pp. 278
–291
.22.
Holmberg
, K.
, Laukkanen
, A.
, Ronkainen
, H.
, Walin
, J.
, Varjus
, S.
, and Koskinen
, J.
, 2006, “Tribological Contact Analysis of a Rigid Ball Sliding on a Hard Coated Surface Part II: Material Deformations, Influence of Coating Thickness and Young’s modulus
,” Surf. Coat. Technol.
0257-8972, 200
(12–13
), pp. 3810
–3823
.23.
Dassault Systemes S.A
, 2008, ABAQUS™: Version 6.6.25.
Yu
, N.
, Bonin
, W. A.
, and Polycarpou
, A. A.
, 2005, “High-Resolution Capacitive Load-Displacement Transducer and Its Application in Nanoindentation and Adhesion Force Measurements
,” Rev. Sci. Instrum.
0034-6748, 76
(4
), pp. 045109
.26.
Oliver
, W. C.
, and Pharr
, G. M.
, 1992, “An Improved Technique for Determining Hardness and Elastic Modulus Using Load and Displacement Sensing Indentation Experiments
,” J. Mater. Res.
0884-2914, 7
(6
), pp. 1564
–1583
.27.
Yeo
, C. D.
, and Polycarpou
, A. A.
, 2007, “A Correction to the Nanoindentation Technique for Ultrashallow Indenting Depths
,” J. Mater. Res.
0884-2914, 22
(9
), pp. 2359
–2362
.28.
Tabor
, D.
, 1951, Hardness of Metals
, Oxford University Press
, New York
.29.
Lee
, K. -M.
, Yeo
, C. -D.
, and Polycarpou
, A. A.
, 2007, “Nanomechanical Properties and Nanowear Measurement for Sub-10-nm Thick Films in Magnetic Storage
,” Exp. Mech.
0014-4851, 47
, pp. 107
–121
.30.
Robertson
, J.
, 2002, “Diamond-Like Amorphous Carbon
,” Mater. Sci. Eng. R.
0927-796X, 37
(4–6
), pp. 129
–281
.31.
Cho
, S. -J.
, Lee
, K. -R.
, Eun
, K. Y.
, Hahn
, J. H.
, and Ko
, D. -H.
, 1999, “Determination of Elastic Modulus and Poisson’s Ratio of Diamond-Like Carbon Films
,” Thin Solid Films
0040-6090, 341
(1–2
), pp. 207
–210
.32.
Callister
, W. D.
, 2000, Materials Science and Engineering
, Wiley
, New York
.33.
Dao
, M.
, Chollacoop
, N.
, Van Vliet
, K. J.
, Venkatesh
, T. A.
, and Suresh
, S.
, 2001, “Computational Modeling of the Forward and Reverse Problems in Instrumented Sharp Indentation
,” Acta Mater.
1359-6454, 49
(19
), pp. 3899
–3918
.34.
Bucaille
, J. L.
, Stauss
, S.
, Felder
, E.
, and Michler
, J.
, 2003, “Determination of Plastic Properties of Metals by Instrumented Indentation Using Different Sharp Indenters
,” Acta Mater.
1359-6454, 51
(6
), pp. 1663
–1678
.35.
Barinov
, S. M.
, 1997, “On the Strain Hardening-Plastic Strain Relation for Nickel Aluminides in Bending Tests
,” J. Mater. Sci. Lett.
0261-8028, 16
(5
), pp. 358
–360
.36.
Karimpoor
, A. A.
, Erb
, U.
, Aust
, K. T.
, and Palumbo
, G.
, 2003, “High Strength Nanocrystalline Cobalt With High Tensile Ductility
,” Scr. Mater.
1359-6462, 49
(7
), pp. 651
–656
.37.
Dowling
, N. E.
, 1999, Mechanical Behavior of Materials
, Prentice-Hall
, Englewood Cliffs, NJ
.38.
Hamilton
, G. M.
, 1983, “Explicit Equations for the Stresses Beneath a Sliding Spherical Contact
,” Proc. Inst. Mech. Eng., Part C: Mech. Eng. Sci.
0263-7154, 197
, pp. 53
–59
.39.
Bhushan
, B.
, 2002, Introduction to Tribology
, Wiley
, New York
.40.
Yu
, N.
, Polycarpou
, A. A.
, and Conry
, T. F.
, 2004, “Tip-Radius Effect in Finite Element Modeling of Sub-50 nm Shallow Nanoindentation
,” Thin Solid Films
0040-6090, 450
(2
), pp. 295
–303
.41.
Brand
, J. L.
, Roy
, M.
, and Frenz
, A. D.
, 2007, “Designing, Modeling, and Testing Particle Robust Air Bearings for Perpendicular Recording Media
,” IEEE Trans. Magn.
0018-9464, 43
(9
), pp. 3791
–3795
.42.
Luan
, B.
, and Robbins
, M. O.
, 2005, “The Breakdown of Continuum Models for Mechanical Contacts
,” Nature (London)
0028-0836, 435
, pp. 929
–932
.43.
Landman
, U.
, Luedtke
, W. D.
, and Gao
, J.
, 1996, “Atomic-Scale Issues in Tribology: Interfacial Junctions and Nano-Elastohydrodynamics
,” Langmuir
0743-7463, 12
(19
), pp. 4514
–4528
.Copyright © 2010
by American Society of Mechanical Engineers
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