Nonlinear dynamic effects at the head-disk interface

Author

Knigge, Bernhard ; Talke, Frank E.

Author_Institution

Center for Magnetic Recording Res., California Univ., San Diego, La Jolla, CA, USA

Volume

37

Issue

2

fYear

2001

fDate

3/1/2001 12:00:00 AM

Firstpage

900

Lastpage

905

Abstract

The contact dynamics of pico sliders is investigated using a high bandwidth laser Doppler vibrometer (LDV) and a high bandwidth acoustic emission (AE) sensor. Sliding contact of the slider near the glide avalanche point is analyzed for a lubricant thickness of 1.5 nm, 2.5 nm, and 3.5 nm, respectively. Slider airbearing modes as well as torsional and bending mode vibrations are investigated as a function of disk velocity and lubricant thickness. Damping of the airbearing pitch and roll frequency is found to increase with increased lubricant thickness. Nonlinear slider/lubricant interactions are observed leading to additional peaks in the LDV spectrum near the bending mode frequency. Nonlinear effects due to slider/lubricant interactions are modeled using a nonlinear stiffness term in the equation of motion. The numerical and experimental results are found to be in good agreement

Keywords

acoustic emission testing; disc drives; hard discs; lubrication; magnetic heads; measurement by laser beam; vibration measurement; 1.5 to 3.5 nm; acoustic emission sensor; airbearing modes; bending mode vibrations; contact dynamics; disk velocity; glide avalanche point; head-disk interface; laser Doppler vibrometer; lubricant thickness; nonlinear dynamic effects; nonlinear stiffness term; pico sliders; roll frequency; torsional vibrations; Acoustic emission; Bandwidth; Frequency; Friction; Laser modes; Lubricants; Rough surfaces; Signal to noise ratio; Surface roughness; Vibrometers;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.917639

Filename

917639