On the Specific Damaging Effects of Surface and Near-Surface Inclusions
The most significant results of an experimental study on the damaging effects of exogeneous ceramic inclusions in nickel-based superalloys are first reported. Attention is focused on some observations which conflict with a too-simple two-dimensional analysis of the problem. A more realistic theoretical treatment is then developed, which allows the calculation of configurational force and torque acting on a near-surface or surface inhomogeneity: the corresponding interfacial discontinuity of the elastostatic “energy—momentum” tensor is shown to be responsible for specific damaging effects of such inhomogeneities which could not be interpreted otherwise.
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