Hard ferrite (ceramic) magnets have been widely applied because of low cost, good magnetic properties and excellent environmental stability since 1950s,
The main raw material of sintered ferrite is orthoferrite, so it cannot be corroded by high temperature, high humidity or chemical substances (except strong acid and alkali);
Sintered ferrites mainly include barium ferrite (BaO•6Fe2O3) and strontium ferrite (SrO•6Fe2O3);
Sintered ferrites are also classified into isotropic and anisotropic..
The magnetic property of isotropic sintered ferrite is weaker relatively, it has the same magnetic properties in any direction, and can be multi-pole magnetized in any direction;
Anisotropic sintered ferrite has higher magnetic properties than isotropic, and can only be magnetized in the direction of magnetic field orientation during molding;
Sintered ferrite has excellent demagnetization impedance and no flux loss before and after assembly and magnetization;
The working temperature of sintered ferrite is -40°C to + 250°C, the temperature coefficient is poor, and the temperature coefficient of Br is -0.2% / °C, it means, when temperature increases 1°C, Br decreases by 0.2%.
