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Ferrite (magnet)
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<p>A ferrite is one of a family of <a href="/facts/Iron_oxide/KDo8hLWn">iron oxide</a>-containing magnetic <a href="/facts/Ceramic/9JKudpqX">ceramic</a> materials. They are <a href="/facts/Ferrimagnetic/sMcg7RYt">ferrimagnetic</a>, meaning they are attracted by magnetic fields and can be <a href="/facts/Magnetization/zxrtXzTN">magnetized</a> to become <a href="/facts/Permanent_magnet/vvrg6VSk">permanent magnets</a>. Unlike many <a href="/facts/Ferromagnetic/fH3HFnSl">ferromagnetic</a> materials, most ferrites are not electrically <a href="/facts/Electrical_conductor/BSuyupLP">conductive</a>, making them useful in applications like <a href="/facts/Magnetic_core/yojywmuo">magnetic cores</a> for <a href="/facts/Transformer/EYYfXWrF">transformers</a> to suppress <a href="/facts/Eddy_current/KvHNx1v7">eddy currents</a>. </p><p>Ferrites can be divided into two groups based on their magnetic <a href="/facts/Coercivity/duBA23fB">coercivity</a>, their resistance to being demagnetized: "Hard" ferrites have high <a href="/facts/Coercivity/duBA23fB">coercivity</a>, so are difficult to demagnetize. They are used to make permanent magnets for applications such as <a href="/facts/Refrigerator_magnet/4WL3E5UY">refrigerator magnets</a>, <a href="/facts/Loudspeaker/tqEjnJ2z">loudspeakers</a>, and small <a href="/facts/Electric_motor/ArD7BGDa">electric motors</a>. "Soft" ferrites have low coercivity, so they easily change their magnetization and act as conductors of magnetic fields. They are used in the electronics industry to make efficient <a href="/facts/Magnetic_core/yojywmuo">magnetic cores</a> called <a href="/facts/Ferrite_core/f60u8q2g">ferrite cores</a> for high-frequency <a href="/facts/Inductor/YnfAXB3x">inductors</a>, <a href="/facts/Transformer/EYYfXWrF">transformers</a> and <a href="/facts/Antenna_(radio)/pGlcXBvc">antennas</a>, and in various <a href="/facts/Microwave/HmVSN31Y">microwave</a> components. </p><p>Ferrite compounds are extremely low cost, being made mostly of iron oxide, and have excellent corrosion resistance. Yogoro Kato and Takeshi Takei of the <a href="/facts/Tokyo_Institute_of_Technology/kqdLTkto">Tokyo Institute of Technology</a> synthesized the first ferrite compounds in 1930. </p>