What are the failure phenomena and causes of magnetic permeability?
(1) Ferrite permeability
The most frequently used high frequency equipment is ferrite magnetic permeability, it is brittle and easy to break, therefore, can not be affected by impact and external forces, but still can be used after the hardened crack block bonding.The main reason for the failure is overheating, the temperature exceeds its Curie point (most of the domestic less than 180℃), the failure, therefore, must be careful not to overheat it.
(2) Silicon steel sheet
Its Curie point is around 700℃, so the temperature is quite high, but it will rust and age, reducing the efficiency of the sensor.Therefore, the silicon steel sheet magnetic permeability should be updated after a certain period of use.The German crankshaft induction heating equipment is equipped with an oscillation factor instrument, which can measure the relative value of the aging of inductor of crankshaft.
(3) Can be processed with paste magnetic permeability
It is made of reducing iron powder and adhesive mixture pressing, its Curie point should be similar to silicon steel sheet, but the adhesive temperature resistance is not high.Therefore, the use temperature of the adhesive should not be exceeded. Taking FLUXTROL products in the United States as an example, the use temperature should not exceed 300 ℃ for a short time and 250 ℃ for a long time.