AA International, Inc.

United States

Ceramic Magnets are also called Sintered Ferrite Magnets. There are mainly two types of ferrite magnets, Barium ferrite (BaO.6Fe2O3) and Strontium ferrite (SrO.6Fe2O3). Compared with other permanent magnets, sintered ferrite magnet is cheap. It is most suitable for most sensitive, but need not very high performance applicaitons. As this is a non-metal magnets, it is the ideal magnets for applications that require non-rusty magnets in humit envirument. Sintered ferrite magnets are widely used in many different applications, such as motors, cars, magnetic selection loudspeakers, and many special applications. Sintered ferrite (ceramic) magnets are also available in forms of isotropic and an-isotropic. The magnetic properties of isotropic ferrite are the same in all directions, therefore they can be magnetized in any pole arrangements. An-isotropic ferrite magnets, on the other hand, can only be magnetized in the direction they are oriented during production, but they have much higher magnetic strength than isptropic ones. CharacteristicsSintered ferrite magnets can be used in between -40 C and +200 CBeing hard and brittle, they can be cut by using diamond tools.The raw material of sintered ferrite magnets is oxide, thus they would not be rusted under severe environment nor affected by many chemicals (except some strong acids).

AlNiCo alloys basically consist of aluminum, nickel, cobalt, copper, iron and titanium. In some grades cobalt andor titanium can be omitted. Also these alloys may contain additions of silicon, columbium, zirconium or other elements which enhance heat treatment response of one of the magnetic characteristics. AlNiCo alloys are formed by casting or powder metallurgical processes. CharacteristicsAlNiCo magnets are very good at temperature properties. Its temperature coefficient is very low, so the change of magnetic properties is low under high temperature. The maximum working temperature can be as high as 400 CThe coercive force of AlNiCo magnets is also very low, so it can be easily effected by reverse magnetic force and impact of iron. This means that they can be easily demagnetized by external influences. For this reason, AlNiCo magnets should not be stored and packed with the same poles opposing to each other.In open circuit, the ration of lengthdiameter (LD) should be at least 4:1. With shorter length, AlNiCo magnets are unstable in open circuit.AlNiCo magnets have good corrosion resistance characteristic. No coating is needed for surface protection.ApplicationsInstrumentsMetersMobile PhonesOdometers