Three dimensional dynamic stress intensity factors are analyzed for a curved crack with a second order perturbation method. The method is extended to obtain an approximate representation of a three dimensional dynamic...Three dimensional dynamic stress intensity factors are analyzed for a curved crack with a second order perturbation method. The method is extended to obtain an approximate representation of a three dimensional dynamic stress intensity factors at the tip of a curved crack. Due to three dimensional curved crack growth the dynamic energy release rate can be calculated by using the Irwin＇s formula. A three dimensional curved crack in materials with inhomogeneous fracture toughness are considered. Paths of a brittle three dimensional curved crack propagating along a welded joint are predicted via the present method, where the effects of dynamic applied stresses, residual stresses, and material deterioration due to welding are taken into considerations.展开更多
The dynamic response of multiple coplanar interface cracks between two dissimilar piezoelectric strips subjected to mechanical and electrical impacts is investigated.Solutions to two kinds of electric boundary conditi...The dynamic response of multiple coplanar interface cracks between two dissimilar piezoelectric strips subjected to mechanical and electrical impacts is investigated.Solutions to two kinds of electric boundary conditions on crack surfaces,i.e.electric impermeable and electric permeable,are obtained.Laplace and Fourier transforms and dislocation density functions are employed to reduce the mixed boundary value problem to Cauchy singular integral equations, which can be solved numerically.The effects of electrical load,geometry criterion of piezoelectric strips,relative location of cracks and material properties on the dynamic energy release rate are examined.展开更多
基金supported by National Natural Science Foundation of China(No.91016026)Henan Province Natural Science Foundation Subsidy Project(No.152300410003)
文摘Three dimensional dynamic stress intensity factors are analyzed for a curved crack with a second order perturbation method. The method is extended to obtain an approximate representation of a three dimensional dynamic stress intensity factors at the tip of a curved crack. Due to three dimensional curved crack growth the dynamic energy release rate can be calculated by using the Irwin＇s formula. A three dimensional curved crack in materials with inhomogeneous fracture toughness are considered. Paths of a brittle three dimensional curved crack propagating along a welded joint are predicted via the present method, where the effects of dynamic applied stresses, residual stresses, and material deterioration due to welding are taken into considerations.
基金Project supported by the Research Grants Council of the Hong Kong Special Administrative Region,China(No.HKUT014/00E)the National Natural Science Foundation of China(No.19772029).
文摘The dynamic response of multiple coplanar interface cracks between two dissimilar piezoelectric strips subjected to mechanical and electrical impacts is investigated.Solutions to two kinds of electric boundary conditions on crack surfaces,i.e.electric impermeable and electric permeable,are obtained.Laplace and Fourier transforms and dislocation density functions are employed to reduce the mixed boundary value problem to Cauchy singular integral equations, which can be solved numerically.The effects of electrical load,geometry criterion of piezoelectric strips,relative location of cracks and material properties on the dynamic energy release rate are examined.
