Fracture Dynamics of a Mode Ⅲ Moving Crack Impacted by Elastic Wave in Functionally Graded Materials

摘要

The dynamic stress field under the SH-waves at the moving crack tip of functionally graded materials is analyzed,and the influences of parameters such as graded parameter,crack velocity,the angle of the incidence and the number of the waves on dynamic stress intensity factor are also studied.Due to the same time factor of scattering wave and incident wave,the scattering model of the crack tip can be constructed by making use of the displacement function of harmonic load in the infinite plane.The dual integral equation of moving crack problem subjected to SH-waves is obtained through Fourier transform with the help of the exponent model of the shear modulus and density,then have some process on the even and odd term of the integral kernel.The displacement is expanded into series form using Jacobi Polynomial,and then the semi-analytic and numerical solutions of dynamic stress intensity factor are derived with Schmidt method.