Crack arrest in Si3N4-based layered composites with residual stress

Effect of macroscopic residual stresses on fracture resistance and crack arrest in non-symmetric Si3N4/Si3N4–xTiN (x=20, 30 wt%) layered specimens was investigated in this study. One of the aims of the work was also an examination of compliance technique to study R-curve effect as applied to layered specimens. A special attention was paid to the development of an analytical method to calculate fracture resistance – crack length dependence in layered structures having different elastic moduli of layers. The validity of the method and its application were examined by calculating stress intensity coefficients for edge-cracked layered specimens and comparison of the results with mechanical characteristics obtained from bending test.