In the present study, scale models of an actual motor grain were studied using internal pressure as was done before. These tests were preceded by two dimensional tension tests on a pie shaped element of a motor cross-section containing a single fin in order to confirm the location of the starter crack. These tests employed the actual motor grain. Subsequently, starter cracks were introduced at these locations in the photoelastic models with new end cap designs and SIF distributions around the ensuing crack fronts were determined. Locations of starter cracks were compared with photoelastic results from uncracked models.
Results suggest consistent trends in crack initiation location and growth.
Proc. of 9th International Conference on Experimental Mechanics,'' Vol. 5, pp. While J was originally defined from energy perspective, it was demonstrated that it could be inferred from load-displacement diagrams. The specimen is considered at fully plastic loading where it is at the state of collapse. The effect of pressure sensitivity is accounted for by using the Drucker-Prager yield criterion for solid materials. Since CT testing is usually conducted on metallic materials, strain-hardening behavior of the material is incorporated in the analysis.