Variational principles, numerical schemes and bounding theorems for deformation by Nabarro-Herring creep

In this paper two variational principles are presented for the analysis of problems in which self diffusion is the dominant mechanism of material redistribution within a solid body. It is demonstrated how these variational principles can be used as the basis for developing numerical procedures and bounding theorems for analysing the response of creeping bodies. The resulting procedures are used to analyse the creep deformation of a regular two-dimensional array of hexagonal grains and the process of void growth when the body contains a uniform distribution of triple-point voids.