Evaluation of Stress Intensity Factor for Small Edge Interface Crack under Thermal Stress

摘要

This paper deals with the analysis of the thermal stress intensity factor for small edge interfacial crack between bonded dissimilar plates subjected to uniform change of temperature by using the crack tip stress method. The stress intensity factor of edge interface crack is strongly controlled by the singular stress field at the interface edge of the bonded plates without the crack when the crack becomes extremely short. In this study, the small edge interface crack problem under thermal stress is solved by superposing the uniaxial tension problem with edge singularity and the uniform stress problem having the boundary condition of temperature change and uniaxial compression. The calculation shows that the stress intensity factors of the small edge interface crack under thermal stress can be evaluated from four factors related only to the Dundursu27 parameters α and β. In addition, the expression of the stress intensity factor for the small edge interface crack under the logarithmic edge singularity is presented when the material combination is α=2β.