An investigation was made of the motion of planar symmetrical and asymmetrical tilt boundaries, in high-purity material with <112>- or <111>-tilt axes, under the influence of an external mechanical stress field. It was found that motion of low-angle grain boundaries, as well as high-angle grain boundaries, could be induced by the imposed external stress. The motion of planar low- and high-angle grain boundaries under the influence of a mechanical stress field could be attributed to movement of the grain boundary dislocations which comprised the structure of the boundary. A sharp transition between low-angle grain boundaries and high-angle grain boundaries was observed at 13.6º. This was apparent from a step in the activation enthalpy for grain boundary motion. For the present boundaries, the transition angle was independent of the tilt axis, impurity content and boundary plane.

Stress Induced Grain Boundary Motion. M.Winning, G.Gottstein, L.S.Shvindlerman: Acta Materialia, 2001, 49[2], 211–9