Chapter 3 – Diffusional Creep

Non-dislocation-based diffusional creep at high temperatures (T ≈ Tm) and very low stresses in fine-grained materials was qualitatively suggested 50 years ago by Nabarro. This was rigorously (quantitatively) proposed and described by Herring. Mass transport of vacancies through the grains from one grain boundary to another was described. Excess vacancies are created at grain boundaries perpendicular to the tensile axis with a uniaxial tensile stress. The theory, however, is controversial.