Accession Number : AD0476901

Title :   STABLE FERRITES FOR R.F. APPLICATIONS.

Descriptive Note : Quarterly rept. no. 5, 1 Jul-30 Sep 65

Corporate Author : INDIANA GENERAL CORP KEASBEY NJ RESEARCH DEPT

Personal Author(s) : O'Neill, Charles F.

Report Date : 30 SEP 1965

Pagination or Media Count : 50

Abstract : Some preliminary data were gathered on another aspect of instability. A.C. drive effects on material MF-9304 were found to amount to a change in micro-o of 0.48%/volt and in Q of 14.9%/volt. The measurements were made without applying a simultaneous d.c. current of 10 milliamps. A cup core die for laboratory use has been made but cup cores of MF-9304 material have so far been made of poor physical quality. Results are incomplete yet in the determination of an optimum iron oxide content for MF-9304. It was again found, however, that deficient iron oxide formulas when fired in nitrogen yield the lowest TF values. A lithia addition to the MF-9304 formula shows some promise of lowering TF values; a TF of 9.9 PPM/C was obtained with a toroid that had a reasonably good micro-oQ curve. A bentonite addition of 10.25 weight per cent gave a material which could be fired to good density at 1095 C and which yielded a TF of 2.3 PPM/C and a uuf micro-oQ product of 66500. At this date the bentonite approach appears to be promising. Loading an epoxy resin with Al2O3 and MgO proved to be an effective way of adjusting the thermal expansion characteristic of the epoxy. A satisfactory plastic has not been found yet, however. A cup core of commercial TC-4 material compensated with an Al2O3 loaded epoxy demonstrated a TC of 0.9 PPM/C over a temperature range -60 C to +50 C. (Author)

Descriptors :   *MAGNETIC CORES), (*FERRITES, HIGH FREQUENCY, STABILITY, TUNED CIRCUITS, SPINEL, MAGNETIC PROPERTIES, PERMEABILITY, IRON COMPOUNDS, OXIDES, NITROGEN, LITHIUM, CLAY MINERALS, EPOXY RESINS, ALUMINUM COMPOUNDS, MAGNESIUM COMPOUNDS, THERMAL EXPANSION, TEMPERATURE, VOLTAGE, DIRECT CURRENT, FERROMAGNETIC MATERIALS, NICKEL ALLOYS, ZINC ALLOYS, VIBRATION, SHOCK(MECHANICS).

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE