Dynamic Analysis And Stability Analysis Of Elastic Elements Made In Giant Magnetostrictive Material

As a kind of particular ferromagnetic material,Giant magnetostrictive materials has been widely used in many field because of excellent characteristics such as large strain,high energy density,small hysteretic loss and less performance degradation in normal atmospheric temperature.It has been used to manufacture a driving element in precision actuator.The magnetostrictive rod and lanminate cantilever beam are key structures in actuator.More and more research has been focused on their working behavior.In this paper,the dynamic response analysis and stability analysis of the magnetostrictive rod,laminate cylindrical shell and bilayer shallow spherical shell in the coupling action of the electric,the magnetic,mechanic and temperature field is studied.The major research work in this paper are showed as follows:(1)The mathematical model about giant magnetostrictive cone rod is built according to the linear magnetoelastic constitutive relationship.The vibration of the cone rod excited by harmonic alternating current is analyzed by applying the analytical method.The amplitude and frequency curve are obtained,and the curves about the rod top displacement and time are also obtained.which can provide evidence to the designing of core rod actuators.(2)According to the quadratic nonlinear constitutive relationship,the mathematical model about the vibration of giant magnetostrictive cylindrical rod in middle and high magnetic field is established,and the temperature field is considered.The vibration of magnetostrictive rod excited by harmonic alternating current is analyzed.The effect of temperature on the periodic solution is discussed.(3)According to the cubic nonlinear constitutive relationship,the mathematical model about the vibration of giant magnetostrictive cylindrical rod in middle and high magnetic field is established,and temperature field is considered.The vibration of magnetostrictive rod excited by harmonic alternating current is analyzed.In this problem,some coefficients in governing equation and boundary condition are periodic variables of time.By applying the regular perturbation method with the help of a small parameter,the approximate solution is obtained.The effect of temperature field on the vibration isanalyzed,which can provide qualitative and quantitative evidence to the designing of cylindrical rod actuators.(4)The free vibration problem of the magnetostrictive laminate cylindrical shell is studied.And the stability problem of the magnetostrictive laminate cylindrical shell under axial magnetic field is discussed.The effect of the shell length on frequency and the critical buckling magnetic field are discussed.(5)The nonlinear buckling problem of bilayer shallow spherical shell made in Tefernol-D and cuprum in uniform temperature field and axial magnetic filed are discussed,the modified interation method is applied to solve the nonlinear boundary problem.The critical buckling temperature is obtained,the characteristic curves are also obtained,and the effect of magnetic field on critical buckling temperature is discussed.