Free-Edge Stress Singularity in Bonded Dissimilar Orthotropic Materials Under Thermal Stress Leading

Abstract

When two dissimilar materials are bonded, thermal stresses develop due to the difference in coefficient of thermal expansion of the materials. In recent years, not only isotropic materials but also anisotropic materials are used for making bonded dissimilar materials. In this study, free-edge stress singularity of bonded dissimilar orthotropic materials under thermal stress loading is investigated theoretically. The thermal stresses show the free-edge stress singularity similar to that under mechanical loading, when the thermoelastic constant stress term is subtracted. Stress distributions on the interface are calculated by using the boundary element method. The value of the order of thermal stress singularity determined by using boundary element results agrees well with the theoretical value obtained by using the characteristic equation. It is shown that the thermal stress singularity disappears for certain ranges of wedge angles of a pair of materials.