Study On Defect Interaction In One-Dimensional Hexagonal Quasicrystal Piezoelectric Material

The interior of the quasicrystal material is prone to various cracks,holes,inclusions and other defects.These defects often lead to material damage.If the effective method is not used to suppress the crack propagation,it will cause immeasurable loss to the project,so study these defects and defect interactions in materials are very meaningful.A lot of work has been done on the single defect problem,but there are not many studies on complicated defect interaction problems.Complex variable function method is one of the basic methods of classical elasticity theory,and it is an effective method for solving the analytical solution of plane elasticity and defect problems.In this paper,the problem of defect interaction in one-dimensional hexagonal quasicrystal piezoelectric material is studied by using complex variable function method.The first chapter introduces the quasicrystal material properties,application,and research progress quasicrystal and quasicrystal piezoelectric material.In the second chapter,the complex potential expressions of the interaction between the screw dislocation and the semi-elliptical hole in the semi-infinite one-dimensional hexagonal quasicrystal piezoelectric material are obtained by introducing the conformal mapping.The effects of geometric parameters on the stress intensity factor,energy release rate and image force are analyzed when the semi-elliptical hole degenerates into a straight crack.Inthethird chapter,thefractureproblem of finite-large one-dimensional hexagonal quasicrystal piezoelectric wedge with screw dislocation under the action of anti-plane load is solved by using complex variable function method.The distribution characteristics and wedge angle of shear stress at different wedge angles are discussed.The effect of size on the field intensity factor.By constructing a new conformal mapping and using analytical continuation technique,the complex potential expressions of the two asymmetric crack interaction problems between the screw dislocation and the elliptical hole are obtained in the fourth chapter.And the corresponding degradation results of Griffith crack with lengtha?10?l₁,elliptical hole and round hole are compared and verified.Combined with numerical examples,the effects of the coupled elastic constant of the phonon-phase field,dislocation points and geometric parameters on field intensity factor and image force are discussed.