Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Ferrite Composition for Use in Bistable Magnetic Circuits

IP.com Disclosure Number: IPCOM000092486D
Original Publication Date: 1966-Nov-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Brownlow, JM: AUTHOR

Abstract

This describes a new family of ferrite compositions. The compositions contain six ingredients: Fe(a), Mn(b), Cd(c), Zn(d), Li(e), La(f), B(g)i, and O(4). The ingredients appear in the composition in the following amounts. Range Preferred Amount Fe(a) 1.5 - 2 1.67 Mnb(b) 0.3 - 1.25 0.9 Cd(c) 0.05 - 0.40 0.15 Li(e) 0.15 - 0.35 0.25 La(f) 0.005 - 0.03 0.010 Bi(g) 0.005 - 0.03 0.02. The composition is manufactured in the usual way and includes the steps of ceramic ball milling, calcining, forming and firing. Firing temperatures can be from 850 degrees C to 1300 degrees C. High temperature firing raises permeability.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 94% of the total text.

Page 1 of 1

Ferrite Composition for Use in Bistable Magnetic Circuits

This describes a new family of ferrite compositions. The compositions contain six ingredients: Fe(a), Mn(b), Cd(c), Zn(d), Li(e), La(f), B(g)i, and O(4). The ingredients appear in the composition in the following amounts. Range Preferred Amount

Fe(a) 1.5 - 2 1.67

Mnb(b) 0.3 - 1.25 0.9

Cd(c) 0.05 - 0.40 0.15

Li(e) 0.15 - 0.35 0.25

La(f) 0.005 - 0.03 0.010

Bi(g) 0.005 - 0.03 0.02. The composition is manufactured in the usual way and includes the steps of ceramic ball milling, calcining, forming and firing. Firing temperatures can be from 850 degrees C to 1300 degrees C. High temperature firing raises permeability. Cooling can be slow or rapid in gaseous atmospheres containing from 10/-2/ mm of oxygen to 760 mm of oxygen.

The arrangement of cations in these new materials is quite different than copper manganese materials. The large amount of lithium causes the Mn/2+/ and Fe/2+/ to be very low and, therefore, the Mn/2+/ on A sites is greatly reduced. The magnetic moments and Curie temperatures are those expected.

Some objectives achieved in this system are low magnetostriction, low firing temperature and easier process control. The materials have a high remanence to saturation flux ratio for use in computer memories. The primary emphasis for core memory use is in low magnetostriction. The properties of the resulting cores of the composition are not altered by static stresses. Also, the mechanical resonance rin...