Ferrites square-loop

The composition and structural properties of ferrites vary with the end use. For square-loop ferrites the Mn0-Fe203 combination is fundamental, together with CuO, MgO, or other oxides as well as with oxides added in doping concentrations. In soft ferrites (high initial permeability, low demagnetizing field, narrow hysteresis loop) manganous oxide and zinc... 

To distinguish among major fields nt applications, ferrites can he separated into live groups Soft, square-loop. hard, microwave, and single-crystal lerrites. 

Lithium ferrite itself (x = 0.5) has a high Curie temperature and can be fabricated so as to give a square hysteresis loop satisfactory for digital-computer memory cores. In this application, the dielectric losses connected with the presence of mobile charge carriers can cause a dramatic loss in core quality. The mobile carriers may be introduced by... 

Ferrites having a square hysteresis loop (e.g. (Mg, Mn, Zn) Fe204), developed for the now outdated computer core memories, have found applications in the form of a toroidal saturable inductor for regulating the output currents in switched-mode power supplies. 

Chem. Ges. 42,2248,1909). The ferrites are synthesized from Fe203 and the oxide, hydroxide, or carbonate of one or more divalent metals, e.g. Ba, Zn, Mn, Ni, Co, Mg or Cu. The firing process must be carefully controlled to maintain the required state of oxidation. Mg-Mn ferrites have a square hysteresis loop BaO-fiFejOj is a hard , or permanent, magnetic material. 

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