Giant magnetostictive driving device

The invention provides a giant magnetostictive driving device, which belongs to the field of giant magnetostictive driving devices, and particularly relates to a giant magnetostictive driving device which adopts a closed type hydraulic micro displacement amplifier as a displacement amplifying mechanism. The giant magnetostictive driving device consists of a giant magnetostictive actuator and the closed type hydraulic micro displacement amplifier, wherein external threads at the lower end of a circular actuator shell in the giant magnetostictive actuator is connected and locked with internal threads at the upper end of a circular amplifier shell in the closed type hydraulic micro displacement amplifier. The giant magnetostictive driving device has the advantages that the displacement output range is large, additional micro displacement of an output end of the giant magnetostictive driving device, which is caused by volume changes of working media in a closed cavity of the closed type hydraulic micro displacement amplifier, can be automatically compensated when the temperature is changed, and the accuracy is high; and a simple and easy temperature control mode is adopted over a giant magnetostictive rod and an independent temperature control system does not need to be provided, so that the realization is relatively convenient.