Measurement of hindered settling in magnetic dispersions

• Published in: IEEE transactions on magnetics Vol. 38; no. 5; pp. 3219 - 3221
• Main Authors: Mercer, T., Bissell, P.R., Gilson, R.G.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01-09-2002; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Atmospheric modeling; Computer simulation; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Dispersion; Exact sciences and technology; Magnetic analysis; Magnetic flux; Magnetic levitation; Magnetic liquids; Magnetic properties and materials; Magnetic recording; Magnetism; Magnetostatics; Materials science and technology; Physics; Stability; Studies of specific magnetic materials; Magnetite; Magnetometry; Richardson-Zaki model; Steinour model; Recording material; Hindered settling; Experimental study; Sedimentation; Magnetic fluids; Suspensions; Kozeny-Carman model; Magnetic recording
• ISSN: 0018-9464; 1941-0069
• DOI: 10.1109/TMAG.2002.802504

The measurement of hindered settling in a /spl gamma/-Fe/sub 2/O/sub 3/ recording media dispersion has been carried out using a scanning column magnetometry technique. From subsequent analysis, a high trapped-liquid estimate (of /spl sim/84% by volume of the settling unit) within the suspension structures was found that compares favorably with a previous computer simulation. Correction of hindered settling models to account for the trapped-liquid gave further confidence in the result. In each case, model parameters reduced near-to, or agreed with, those found originally in simple systems that contain little-to-no trapped-liquid.