ABSTRACT
This chapter brings out the detailed design and analyses of tubular socket joints with functionally graded adhesive bond. While designing the tubular socket joint, an finite element (FE)-based simulation technique is developed to study the onset and growth of adhesion/interfacial failures in functionally graded bonded tubular socket joints. The developed FE model provides sufficient scope for a detailed design and analysis of the bonded tubular socket joint in terms of stress analysis within the joint, studying the interfacial failure growth characteristics and investigating the effect of graded adhesive on the growth of interfacial failures. The strain energy release rate (SERR) components calculated using modified crack closure integral (MCCI) vis-à-vis virtual crack closure technique (VCCT) have been used as the characterizing parameters for assessing the growth of interfacial failures in the present analysis. The material-tailored bond line has been considered for the present investigation for improved joint structural integrity. Under three-dimensional stress states in the coupling region, the initiation of interfacial failures at the tubes/socket-adhesive interfaces has been evaluated. It has been observed that the possibility of interfacial failure initiation would be from the free edges of the tube–adhesive interfaces of the bonded tubular socket joint under axial loading. The growth of adhesion failure in the tubular socket joint is performed by simulating pre-embedded interfacial failures near the free edges of the coupling region. The SERR, which is one of the key parameters responsible for the propagation of interfacial failure, is computed using the MCCI vis-à-vis VCCT.
