In this paper, the stress intensity factors (SIFs) for an interfacial notch in a bi-material joint have been calculated using the experimental method of photoelasticity. A bi-material Brazilian disc specimen with a central interface notch was employed to determine the SIFs for different mode mixities. In this approach, SIFs were calculated experimentally for an Al/Polycarbonate bi-material Brazilian disc specimen and two different loading angles (i.e. modes I and II dominated loading conditions). The results of experimental approach were then compared with the numerical values of finite element method. Experimental results were in good consistency with the numerical values.

The effects of mismatch parameters on isochromatic fringe patterns were studied using the technique of photoelasticity. First, the mathematical equations of isochromatic fringes were derived for singular stress field near a bi-material notch. These equations were used to study the effects of mismatch parameters on the shape of isochromatic fringes theoretically. Analytical results indicated that the mismatch parameters have a significant effect on the shape of the isochromatic fringe patterns around the bi-material notch tip. In order to assess the accuracy of the analytical results, a photoelastic test program was conducted on the V-notched bi-material Brazilian disc specimens. A very good agreement was shown to exist between the experimental results and the analytical reconstructions.