Magnetoresistance magnetic material is a significant magnetoresistance effect. Change in resistance of a ferromagnetic material when subjected to external magnetic field caused by the called magnetoresistance effect. Regardless of the direction of the magnetic field is parallel or perpendicular to the current, will produce magnetoresistance effect. The former (parallel) called vertical magnetic field effects, the latter (vertical) called transverse magnetic field effects. Usually ferromagnetic material magnetic resistivity (resistance change caused by the magnetic field and when no magnetic field resistance ratio) of less than 8% at room temperature, at a low temperature can be increased to more than 10%. Have practical magnetoresistance materials are nickel and nickel-cobalt-iron-based magnetic alloys. Magnetic resistivity at room temperature nickel-iron permalloy of about 1% to 3%, if added to the alloy of copper, chromium or manganese, can increase the resistance; high-nickel-cobalt alloy resistivity, up 6% . Compared with the use of other magnetic effect, magnetoresistance effect is made use of a transducer and a sensor, which device is simple, speed and frequency insensitive. Magnetoresistive materials have been used in the manufacture of magnetic recording heads, magnetic bubble detector and a magnetic film memory reads and so on. Changzhou magnetic, electrical magnetic steel sheets, the second product Magnet www.ryrfsd.com