Wide-temperature range, high-magnetic permeability and low-distortion soft magnetic ferrite

Abstract

The invention discloses a wide-temperature range, high-magnetic permeability and low-distortion soft magnetic ferrite. The soft magnetic ferrite is prepared from principal components and auxiliary components, wherein the principal components comprise the following components (in form of oxide) in mole percentage: 52.7 to 53.5 mol percent of Fe2O3, 22.5 to 24 mol percent of ZnO, and balance of MnO; the auxiliary components comprise the following components (in form of oxide) in weight percentage: 0.08 to 0.2 weight percent of SnO2, 0.04 to 0.06 weight percent of CaO, and 0.03 to 0.06 weight percent of V2O5. The soft magnetic ferrite has the characteristics of an initial permeability (25 DEG C) of 6,000 + / - 25 percent and an initial permeability more than 5,000 at the temperature of between - 55 and 85 DEG C, a material hysteresis constant (25 DEG C, B1 is equal to 1.5 mT, and B2 is equal to 3mT) of less than 0.3*10<-6> / mT, a relative loss factor (25 DEG C, 100 KHZ) of less than 10*10<-6>, and a Curie temperature of more than 125 DEG C.

Description

technical field [0001] The invention relates to a soft ferrite with wide temperature, high magnetic permeability and low distortion, especially the soft ferrite suitable for making magnetic cores of small pulse transformers. Background technique [0002] Pulse transformers are widely used in communication, green lighting and other fields. With the continuous increase in the amount of outdoor facilities, new requirements are put forward for the temperature characteristics of pulse transformers, especially in the range of -55°C to 85°C. As an important part of pulse transformers, soft ferrite cores require both the initial magnetic The high conductivity requires good temperature stability of the initial magnetic permeability of the material. Especially in the field of military industry, the requirements for temperature stability are particularly high. The initial permeability of traditional high-permeability soft ferrite can reach 15,000-30,000 at 25°C, however, at -40°C, th...

AI Technical Summary

Problems solved by technology

The initial permeability of traditional high-permeability soft ferrite can reach 15,000-30,000 at 25°C, however, at -40°C, the initial permeability has dropped below 5,000, and at -55°C, the permeability Rate has dropped below 4000

In order to maintain the necessary inductance at low temperature, the pulse transformer must increase the number of turns of the primary winding or use a larger magnetic core, which is unfavorable to the design and use of the pulse transformer

Although the initial permeability of some high-permeability soft ferrites at low temperature (-40°C) is greater than 5000, such as T56 from EPCOS, their Curie temperature is lower than 100°C, which is not very practical.

In addition, some soft ferrites have high initial permeability, but the hysteresis constant and relative loss factor of the material are relatively high, resulting in relatively large distortion of pulse broadband transformers during signal conversion.

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