Nano-asperity contact analysis and surface optimization for magnetic head slider/disk contact

doi:10.1016/S0043-1648(95)06902-X

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Volume 202, Issue 1, 30 December 1996, Pages 83-98

https://doi.org/10.1016/S0043-1648(95)06902-X Get rights and content

Abstract

NiP coated AlMg (NiP) and glass-ceramic (GC) substrates for magnetic recording are measured by an atomic force microscope (AFM) using different scan sizes and sampling resolution. AFM measurements of the NiP and GC surfaces reveal finer and finer details as the sampling interval decreases and that the GC surface contains more high frequency details than the NiP surface. A three-dimensional numerical rough surface contact model (X. Tian and B. Bhushan, ASME J. Tribol., 118 (1996) 33–42) is used to perform contact analysis on the NiP and GC surfaces to study the effect of sampling resolution on contact pressure and contact area. The contact analysis shows that contact pressure increases and contact area decreases as the sampling interval decreases and asperity contact starts from plastic deformation, the scale of which depends on the different surface topographical structures. The analysis also shows that a high frequency structure will facilitate plastic deformation which is not desired for head/disk durability. The stiction in rough surface contact problem is also considered using a numerical stiction model (X. Tian and B. Bhushan, J. Phys. D: Appl. Phys., 29 (1996) 163–178). The stiction model is used to highlight how stiction can be assessed by the bearing ratio of a surface and how stiction is affected by the skewness of surface height distribution. Stiction analysis on two GC surfaces with different skewness shows that a surface with positive skewness has less stiction. A uniform patterned texture with an optimum number of identical asperities (such as produced by laser texturing) appears to be an ideal surface.

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Nano-asperity contact analysis and surface optimization for magnetic head slider/disk contact

Abstract

Wear

Wear

Wear

Int. J. Mech. Sci.

Wear

Stiction at the Winchester head/disk interface

IEEE Trans. Mag.

Tribology and Mechanics of Magnetic Storage Devices

The stiction between magnetic recording head and thin film disks

Liquid-mediated adhesion at the thin-film magnetic disk/slider interface

ASME Journal of Tribology

A model for the effect of humility on stiction of the head/disk interface

Influence of roughness on head/disk stiction induced by a mobile lubricant film

Adv. Info. Storage Syst.

Lubricant performance in magnetic thin film disks with carbon overcoat, Part I: Dynamic and static friction

ASME Journal of Tribology

Lubricant performance in magnetic thin film disks with carbon overcoat. Part II: Durability

ASME Journal of Tribology

Texture optimization on circumferentially textured disk surface for contact start/stop performance

Adv. Info. Storage Syst.

The dependence of stiction and friction on roughness in thin-film magnetic recording disks

J. Appl. Phys.

Effect of relative humidity on friction behavior of the head/disk interface

IEEE Trans. Mag.

The role of relative humidity, surface roughness and liquid build-up on static friction behavior of the head/disk interface

ASME Journal of Tribology

Role of mechanical properties and surface texture in the real area of contact of magnetic rigid disks

ASME J. Tribol.

Contact of nominally flat surfaces

A meniscus model for optimization of texturing and liquid lubrication of magnetic thin-film rigid disks

Tribol. Trans.