Journal of the Society of Materials Science, Japan
Online ISSN : 1880-7488
Print ISSN : 0514-5163
ISSN-L : 0514-5163
Preparation and Control of Magnetic Properties of Ultrafine Iron Particles by Pyrolysis of Fe(CO)5
Yoshiaki SAWADAYoshiteru KAGEYAMAMasashi IWATAShigehisa HARADAAkira TASAKI
Author information

1994 Volume 43 Issue 495 Pages 1609-1614


A technique for controlling primary particle diameter, secondary particle length and magnetic properties of ultrafine iron particles prepared by pyrolysis of Fe(CO)5 has been studied. A relation between fractal dimension as a parameter of shape of the secondary particles and magnetic properties has been also studied. The length of secondary particles is closely related in the primary particle diameter; the larger the diameter, the longer the length. It is affected by the feed concentration, residence time and pre-decomposition ratio of Fe(CO)5. The coercive force of the iron particle powder reaches its maximum value of 120kAm-1 at the primary diameter of 20-25nm. The squareness Br/Bm of video tapes is improved by using longer secondary particles. It is also improved by using particles with smaller fractal dimension. The shape of secondary particles can be characterized by using fractal dimension; the smaller the dimension, the larger the squareness of video tapes.

Information related to the author
© by The Society of Materials Science, Japan
Previous article Next article