Free-Edge Stless Singularity of Bonded Dissimilar Matelials with an lnterlayer under Thermlal Stress Loading
Seiji IOKA, Takahiro SAKAI and Shiro KUBO
Abstract:Free-edge stress singularity usually develops near the edge of interface of bonded dissimilar materials. Because of the difference of the coefficient of the thermal expansion of the materials, the residual stress may develop when two materials are bonded. To defuse the residual stress, an interlayer may be inserted between the two materials. Stress distribution near the edge of the interface in the presence of the interlayer is very important to evaluate the strength of the bonded dissimilar materials. In this study, stress distribution on the interfaces of the bonded dissimilar materials with an interlayer under thermal stress loading was calculated by using the boundary element method. An effect of an interlayer on the stress distributions on the interface was examined numerically. It was found that the influence of the interlayer on the stress distribution was limited within a region where distance from interface edge is smaller than the interlayer thickness. Stress distribution around the edge of the interface of the bonded dissimilar materials with an interlayer can be normalized by the parameters of the singularity and the thermoelastic constant stress term of the bonded dissimilar materials without an interlayer. Key Words:Free-edge stress singularity, Bonded dissimilar materials, Thermal stress, Interlayer, Boundary element method