A decagonal quasicrystal, which is weakened by an arc-shaped crackpenetrating through the solid in the period direction, and which is subjected to remote uniformphonon stresses, is investigated by applying the complex...A decagonal quasicrystal, which is weakened by an arc-shaped crackpenetrating through the solid in the period direction, and which is subjected to remote uniformphonon stresses, is investigated by applying the complex variable method which is just developed bythe authors. It is found that the phonon and phason stresses near the crack tips exhibit inversesquare root singularities. The four complex stress functions characterizing the phonon and phasonfields are derived. Explicit expressions for the phonon and phason stress intensity factors, crackopening displacements and energy release rate are also presented.展开更多
The scattering of SH wave by a cylindrical piezoelectric inclusion partially debonded from its surrounding piezoelectric material is investigated using the wave function expansion method and singular integral ...The scattering of SH wave by a cylindrical piezoelectric inclusion partially debonded from its surrounding piezoelectric material is investigated using the wave function expansion method and singular integral equation technique. The debonding regions are modeled as mul- tiple arc-shaped interface cracks with non-contacting faces. By expressing the scattered ?elds as wave function expansions with unknown coe?cients, the mixed boundary value problem is ?rstly reduced to a set of simultaneous dual series equations. Then dislocation density functions are introduced as unknowns to transform these dual series equations into Cauchy singular integral equations of the ?rst type, which can be numerically solved easily. The solution is valid for arbi- trary number and size of the debonds. Finally, numerical results of the dynamic stress intensity factors are presented for the cases of one debond and two debonds. The e?ects of incidence direc- tion, crack con?guration and various material parameters on the dynamic stress intensity factors are respectively discussed. The solution of this problem is expected to ?nd applications in the investigation of dynamic fracture properties of piezoelectric materials with cracks.展开更多
基金Project supported by the National Excellent Young Scholar Science Fund of China(No.10125209)the Teaching and Research Award Fuud for Outstanding Young Teachers in High Education Institutions of the Ministry of Education of China
文摘A decagonal quasicrystal, which is weakened by an arc-shaped crackpenetrating through the solid in the period direction, and which is subjected to remote uniformphonon stresses, is investigated by applying the complex variable method which is just developed bythe authors. It is found that the phonon and phason stresses near the crack tips exhibit inversesquare root singularities. The four complex stress functions characterizing the phonon and phasonfields are derived. Explicit expressions for the phonon and phason stress intensity factors, crackopening displacements and energy release rate are also presented.
基金Project supported by the Research Fund for Doctors of Hebei Province China (No. B2001213).
文摘The scattering of SH wave by a cylindrical piezoelectric inclusion partially debonded from its surrounding piezoelectric material is investigated using the wave function expansion method and singular integral equation technique. The debonding regions are modeled as mul- tiple arc-shaped interface cracks with non-contacting faces. By expressing the scattered ?elds as wave function expansions with unknown coe?cients, the mixed boundary value problem is ?rstly reduced to a set of simultaneous dual series equations. Then dislocation density functions are introduced as unknowns to transform these dual series equations into Cauchy singular integral equations of the ?rst type, which can be numerically solved easily. The solution is valid for arbi- trary number and size of the debonds. Finally, numerical results of the dynamic stress intensity factors are presented for the cases of one debond and two debonds. The e?ects of incidence direc- tion, crack con?guration and various material parameters on the dynamic stress intensity factors are respectively discussed. The solution of this problem is expected to ?nd applications in the investigation of dynamic fracture properties of piezoelectric materials with cracks.
