Stress intensity factor of an interface crack in a bonded plate under uni-axial tension

Although a lot of interface crack problems were previously treated, few solutions are available under arbitrary material combinations. This paper deals with a central interface crack in a bonded infinite plate and finite plate. Then, the effects of material combinations on the stress intensity factors are discussed. A useful method to calculate the stress intensity factors of an interface crack is presented with focusing on the stress at the crack tip calculated by the finite element method. For the central interface crack, it is found that the results of bonded infinite plate under remote uni-axial tension are always depending on the Dundurs' parameters a, ß and different from the well-known solution of the central interface crack under internal pressure that is only depending on β. Besides, it is shown that the stress intensity factor Ft of bonded infinite plate can be estimated from the stress of crack tip in the bonded plate when there is no crack. It is also found that dimensionless stress intensity factor F1<1 when (α+2β) (α-2β) >0, Ft>1 when (α+2β)(α- 2β)<0, and F1 = 1 when (α + 2β)(α-2β)= 0.