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Many applications of ceramics in wear and impact environments involve tensile and shear loading. The effect of mixed mode loading on the stress intensity factors in NBD 300 silicon nitride disks is studied using the Brazilian disk test. The predictions from the various analytical solutions for stress intensity factors in mixed mode loading are compared by investigating the effect of loading angle (and hence mode mixing) on the stress intensity factors in each case. Stress intensity factors are also computed from a three-dimensional finite element model simulation of the measured crack dimensions under the load that induced fracture in the disks. The analytical and experimental approaches are compared. The analyzed results show that any mixed mode failure in NBD 300 disks is best characterized by a critical strain energy release rate approach. The implications of these results to analyzing the failure of components …