Deformation of Interparticle Necks by Diffusion‐Controlled Creep

The deformation of a neck between two spherical particles of the same size by coupled grain‐boundary and surface diffusion has been simulated numerically through the finite‐difference method. In the case of pure sintering where there is no applied stress, the results agree quite well with simple analytical models. When a force is applied, it is found that they do not deform as truncated spheres, even when surface diffusion is much faster than grain‐boundary diffusion. Expressions are given representing the rate of approach of the particles and the rate of growth of the neck as a function of the current neck radius and the applied stress.