The Effect of Sintering Atmosphere on the Magnetic Properties of MnZn Ferrites

The effects of phosphorous pentoxide on the properties of highly permeable MnZn ferrites have been investigated in this study. It was found that P2O5 addition had a pronounced effect on promoting crystalline grain growth. At the same time, porosity had an initial decrease followed by a subsequent increase with the increase of P2O5 content. Consequently, the initial permeability first increased, and then gradually decreased. Magnetic loss of the samples was also influenced by both grain size and porosity. With 0.06wt% P2O5 addition, the initial permeability reached to the maximum and the magnetic loss declined to the least. Porosity was the dominating factor to determine the ηB (hysteresis material constant) property of the ferrites. With 0.04wt% P2O5 addition, porosity decreased to its bottom, accordingly, the ηB value decreased to the least. Synthetically considering high initial permeability, low ηB value and good permeability frequency characteristic, the content of P2O5 addition had better be kept at 0.04wt%.

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Effect of dopants on the magnetic properties of MnZn ferrites for high frequency power supplies

IEEE Transactions on Magnetics ◽

10.1109/20.364767 ◽

1995 ◽

Vol 31 (2) ◽

pp. 950-953 ◽

Cited By ~ 44

Author(s):

A. Znidarsic ◽

M. Limpel ◽

M. Drofenik

Keyword(s):

Magnetic Properties ◽

High Frequency ◽

Power Supplies ◽

High Frequency Power ◽

Mnzn Ferrites ◽

Frequency Power

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Effect of Calcination Conditions on the Magnetic Properties of MnZn Ferrites Powders Produced by Co Precipitation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.498-499.119 ◽

2005 ◽

Vol 498-499 ◽

pp. 119-124 ◽

Cited By ~ 7

Author(s):

S.R. Janasi ◽

Daniel Rodrigues ◽

Fernando José Gomes Landgraf

Keyword(s):

Magnetic Properties ◽

Nitrogen Atmosphere ◽

Coprecipitation Method ◽

Ceramic Method ◽

Calcination Temperatures ◽

Metallic Oxides ◽

Fine Particle Size ◽

Vibration Sample Magnetometry ◽

Co Precipitation ◽

Mnzn Ferrites

MnZn ferrites are conventionally produced by the ceramic method that involves the solid state reaction of metallic oxides or carbonates at high temperatures. The particles obtained by this method are rather large and non-uniform in size. In order to overcome the difficulties arising out of the ceramic process, the coprecipitation method has been used as an alternative route to produce chemically homogeneous powders with fine particle size. In this work MnZn ferrites powders were produced by the coprecipitation method. The calcination conditions, such as temperature (900oC to 1100oC) and atmosphere (air and nitrogen), were investigated. X ray diffractometry, scanning electron microscopy, thermomagnetic analysis and vibration sample magnetometry were used to characterize the obtained samples. The results indicated that when the samples were calcined in nitrogen atmosphere, the ferrite formation occurred at low calcination temperatures and presented better magnetic properties than those calcined in air.

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