After several seconds of electric pulsing, the holding force of the electric permanent magnetic chuck will be produced by high performance permanent magnet, needing no power supply; the magnetic block can be processed, removed and replaced at will, facilitating the processing of irregular working pieces; the rapid positioning and clamping can save more than 80% of the time; the military-used high performance aviation connector eliminates the trouble of wire dragging in machining process; there is no residual magnetism after loss of field, effectively ensuring the working pieces not being scratched; therefore, electric permanent magnetic products have the incomparable advantages of strong energy, security, sustainability, reliability, no residual magnetism, no magnetic scattering