A compact solution for the interface corner stress intensity factor of a cylindrical butt joint

Abstract

A cylindrical butt joint is widely utilised in bi-materials structures. Numerous examples can be found in micro-electronics, medicine and composite areas. Such bi-material structures normally have a very strong stress concentration at the interface, which often characterised by linear solutions of the theory of elasticity leading to the appearance of stress singularities. These singular solutions play a very important role in failure assessment of such joints by fracture mechanics approaches. In this paper we develop a compact solution for the generalized stress intensity factor at the interface of a cylindrical bi-material joint loaded by remote tensile loading parallel to the axis of symmetry. Based on a careful numerical modelling, a simple equation maintaining simplicity and accuracy over the wide range of problem’s variables is suggested. Furthermore, the existence of scale effect on the interface corner stress intensity factor for a cylindrical butt joint structure is also discussed in detail.