Permanent magnet is indispensable in automobile parts and electronic components. The following types are commonly used:

1)Ferrite sintered permanent magnet (F);

2)Ferrite bonded permanent magnet (BF);

3)Neodymium-iron-boron wound permanent magnet (R);

4)Ndfeb bonded permanent magnet (BR).

The soft magnetic materials that make up the magnetic loop are required to conduct well, so as to give full play to the magnetic properties of permanent magnets built into the magnetic yoke.Furthermore, they are of the highest temperature, general in the enclosure for the 353 k (80 ℃), the engine room is 398 k (125 ℃).In order to ensure the normal operation of automobiles under various operating conditions and meteorological conditions, the permanent magnet used in automobile parts and components is required to have the heat resistance and reliability above the highest temperature.