Stress concentration analyses of bi-material bonded joints without in-plane stress singularities

The problem of stress concentration in bi-material bonded joint is investigated under the condition of without stress singularities. Disappearance conditions of stress singularity near interface corners and edges are determined based on analyses of eigenvalue equations. Straight-side and curved interface of materials are designed for the bi-material models to avoid singular stress fields around the interface corner and edge. Assuming that one stress component or combined stresses are responsible for failure at or near the interface, the stress concentration becomes critical for the design of bi-material joints with higher interfacial strength. Numerical results show that the stress state near the interface depends strongly on both the interface geometry and the combination of materials, and stress concentration may always occurs at or near the interface. Emphasis is placed on the necessity for geometric optimization of an interface in order to design singularity-free junction with higher interfacial strength.