A magnetometer for the rapid and nondestructive measurement of magnetic properties on rigid disk media

Author

Johnson, K.E. ; Kerr, M.G.

Author_Institution

IBM Corp., Rochester, MN, USA

Volume

26

Issue

5

fYear

1990

fDate

9/1/1990 12:00:00 AM

Firstpage

2565

Lastpage

2567

Abstract

A magnetometer that allows for rapid and nondestructive measurement of magnetic properties on rigid-disk media is described. A rotating wheel containing erase, record, and read heads generates a remanence transfer curve from which the remanence thickness product, the remanent coercivity, and the coercive squareness can be calculated. The measurement takes about 70 s and serves as an especially important tool for process engineers controlling the magnetic properties of the disk-sputtering process. The essence of the measurement is the readback analysis at different write currents of a 25-μm-long recorded transition with width equal to the width of the record head (in this case 19 mm). By moving the disk to different positions, magnetic properties of rigid disks can be mapped

Keywords

magnetic disc storage; magnetic recording; magnetometers; nondestructive testing; 19 mm; coercive squareness; disk-sputtering process; erase; magnetic properties; magnetometer; nondestructive measurement; process engineers; read heads; readback analysis; record head; recorded transition; remanence thickness product; remanence transfer curve; remanent coercivity; rigid disk media; rotating wheel; write currents; Coercive force; Feedback; Magnetic analysis; Magnetic heads; Magnetic properties; Magnetic recording; Magnetometers; Remanence; Sputtering; Wheels;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.104799

Filename

104799