Fundamental Theory And Experiments Study Of Giant Magnetostrictive Actuator

Giant Magnetostrictive Material (GMM ) is a new functional material which has bi-directional transduction effects, it can be made into Giant Magnetostrictive Actuator (GMA) by using the direct effect, also can be made into kinds of sensors by using the converse effect. Compared with piezoelectric actuator, GMA owns the advantage of larger load capacity, rapider response, higher reliability and lower voltage drive, etc, It has a promising prospect in precision positioning, active noise and vibration control and fluid control (pump, valve) fields. This dissertation emphasizes on axial moving type GMA , studies theory for designing GMA, performance optimization and hysteresis control. We successfully developed a magnetostrictive precision micro-displacement actuator prototype and a general experiment table for GMA. These work offer good and universal guidance for design and application of GMA; Moreover, how the bias condition affects the converse effect of GMA is also studied, which provides a valuable reference for the design of self-sensing GMA, and then some new approaches of realizing the self-sensing GMA are explored in this dissertation.In the first chapter, the development background of modern actuator, the research situation of the application of GMM and self-sensing actuator in China and oversea are presented, some problems within GMA research are pointed out, the project significance and main contents of the research are provided.In the second chapter, the basic properties of GMM are introduced, the magnetostrictive phenomenon is explained by magnetic domain theory, and the linear piezo-magnetic equations are provided, then the connotation of some key parameters of GMM and their relations are analyzed.In the third chapter, theory and methods for designing the axial moving type GMA are presented, including the frame design of GMA, the geometric parameter design of GMM rod and magnetic field distribution on the cross section, the geometric parameter design and optimization of the drive coil, magnetic circuit design, pre-stress mechanism design, a new cooling method using water filled in the chamber of the coil and the temperature control system are provided.In the fourth chapter, the general experiment table for GMA based on virtual instrument techniques is build up. The influences of pre-stress, bias magnet, and load to GMA are provided; Lump parameter kinetic model of GMA is build up, and transfer function of GMA is attained by frequency response measurement; Magnetomechanical coupling factor is attained through electrical impedance...