Interface Crack In Dissimilar Materials Research Articles

등속 진전하는 이방성 이종재 접합계면 균열에 대한 연구

The displacement vector field can be represented in terms of a scalar potential Φ and a vector potential Ψ. The scalar potential Φ is related to dilatational waves and the vector potential Ψ is related to rotational waves. Using these two complex displacement potentials, the stress and displacement fields for steadily growing interface cracks in dissimilar materials are obtained. The energy release rate for steadily growing interface cracks in dissimilar materials are also obtained. And with photoelastic isochromatic patterns simulated by computer graphics, the stress intensity factors are discussed.

Stress Intensity Factor Analyses of Bimaterial Interface Cracks Based on Interaction Energy Release Rate and Boundary Element Sensitivity Analysis.

This paper presents a method for evaluating stress intensity factor of interface cracks in dissimilar materials by using interaction energy release rate. Interaction energy release rate is defined based on the energy release rates of a crack of a body. corresponding to two independent loading conditions, and can be evaluated as a sensitivity of the potential energy with respect to the crack length. Since the potential energy is written by using a boundary integral in terms of the traction and the displacement over the boundary of the body, the interaction energy release rate can also be written in the form of a boundary integral for the displacement, the traction, and their sensitivity coefficients for the crack length. The boundary element sensitivity analyses are used to calculate these quantities accurately. Some numerical demonstrations show that the present method can give accurate results for the stress intensity factors of various interface cracks between dissmilar materials under coarse mesh discretizations.

Efficient boundary element analysis of stress intensity factors for interface cracks in dissimilar materials

The stress intensity factors of an interface crack in dissimilar materials are clarified and an extrapolation method to determine the stress intensity factors of an interface crack is proposed. The BEM using Hetenyi's fundamental solution is applied to crack problems in dissimilar materials and various numerical results of the stress intensity factors obtained are compared with exact solutions and other results. It is confirmed that the present method is very useful for the analysis of the interface crack problems.

Boundary element analysis of stress intensity factors for an interface crack in dissimilar materials.

This paper describes the boundary element elastostatic analysis of a crack along the straight interface between two dissimilar materials. It is well known that the interface crack has an oscillation singularity at the crack tip which is quite different from a crack in homogeneous materials. Therefore, the definition of the stress intensity factor is not clarified yet and it is very difficult to analyze the interface crack by the numerical methods, such as FEM and BEM. We proposed a method to determine the stress intensity factors K1 and K2, for the interface crack by means of extrapolating the solutions at the points apart from the crack tip to avoid the oscillation singularity. This method can be widely applied to the BEM and also FEM analyses with any changes of the programmes. It is confirmed that the present results of the stress intensity factors for an interface crack in the infinite plate are completely consistent with the exact solutions. The stress intensity factors for various interface cracks in the finite plate and the adhesive joint are analyzed by the present method and BEM analyses, which is specially developed for this study.