A study of the behaviour of subinterface cracks in bimaterial plates

• Published in: Engineering fracture mechanics 1998, Vol.59 (2), p.241-252
• Main Authors: Venkatesha, K.S., Ramamurthy, T.S., Dattaguru, B.
• Format: Article
• Language: English
• Subjects: bimaterial interface, subinterface cracks, SERR, contact zone, virtual crack extension, finite element analysis
• ISSN: 0013-7944; 1873-7315
• DOI: 10.1016/S0013-7944(97)00129-X

In this paper, finite element analysis of a subinterface crack in a bimaterial plate is presented with a view to quantify the definitive trends as the subinterface crack approaches the interface. The material properties of the bimaterial plate were chosen such that the crack-tip contact zones are large for the corresponding case of a bare interface crack problem. Both mode I and mode II loadings were studied separately and strain energy release rate (SERR) components were calculated when the subinterface crack lies parallel and at a distance “ s ” from the interface for various virtual crack extension (Δ a) values. The SERR components at the subinterface crack tip were evaluated using a special generalized modified crack closure integral (GMCCI) algorithm, developed in an earlier paper by the present authors. The SERR components were evaluated for several s values and the study has clearly brought out the behaviour of SERR components as the distance of the subinterface crack s decreases to zero from a value of the order of the crack length. By carrying out a systematic finite element study of the variation of SERR components with Δ a/ a for various s values, the bare interface crack behaviour with stress-free crack faces reported in the literature was reproduced as s→0 in the present problem. Numerical results are presented for a specially designed problem with large crack-tip contact zones.