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Page count: 22

The most dominant singular stress distributions caused by grain-boundary sliding accommodated by power-law creep have been determined at hard grain-boundary particles and at triple grain junctions, where cavitation and eventual creep cracking are frequently observed. Finite element computations have been used to connect these local stresses to the far-field stresses. These finite element analyses incorporate a specially formulated power-type singularity element, a new method of simulating periodicity and symmetry boundary conditions, a scheme for automatic variable step selection for stable time integration, and a method to bypass the influence of incompressibility. The deviatoric stresses obtained from the finite element results show very good agreement with the dominant singularity solutions, and provide accurate estimates of the generalized stress intensity factors.