ON THE STRESS CONCENTRATION ALONG INTERFACES WITHOUT STRESS SINGULARITIES

The problem of stress concentrations in a bi-material bonded joint is investigated numerically using finite element analysis under the condition of without stress singularities. Firstly, the geometry and combination of materials for eliminating stress singularity near interface corners and edges in a joint are determined based on analyses of eigenvalue equations. Several geometric models of a bi-material bonded joint with constant section but without stress singularities are developed according to the solutions. Subsequently, the stress distributions along the interface of the models are analyzed under the axisymmetric assumption. The emphasis is placed on the effects of material combinations and the interface shape on the stress concentrations along the interface. The results show that the stress concentration is inevitable due to the mismatch of materials. The degree of the stress concentration depends on both material combination and the interface geometry. It is expected that this work could provide useful information for geometric optimization of the interface, with the goals of designing bi-material joints with higher interfacial strength.