Evaluation of first non-singular stress term in bi-material notches

The influence of the first non-singular stress term on the stress field near the bi-material notches has been evaluated. An extensive study has been carried out on the higher order eigenvalues and their correlation with the notch angle and the material combination of the bi-material joints. The coefficients of singular and non-singular terms of the stress field were then calculated for two laboratory specimens with different notch angles and material configurations of the bi-material joints using the displacement field obtained from finite element analysis. It was shown that considering only the two singular terms of a bi-material notch in order to characterize the near stress field may lead to significant errors. Adding the first non-singular term called I-stress, however, could improve the accuracy of the stresses near the notch tip efficiently. Therefore, a three-parameter model including the two singular terms and the I-stress term for predicting the onset of brittle fracture in the bi-material notched components is likely to be more accurate than the classical models which are based only on the singular terms.