Influence of triple junctions on grain boundary motion

The paper is dedicated to the steady state motion of the grain boundary systems with the triple junctions. The main features of one of the systems where the steady state motion is possible are considered. In the experimental part the special technique of in-situ observations and recording of the triple junction motion and the results of the experiments on the tricrystals of Zn are described comprehensively. It was shown, in particular, that the described method makes it possible to study the motion of a grain boundary system with a triple junction and, what is of importance to measure its mobility. The shape of the moving half-loop in the tricrystal fits the theoretically calculated. The transition from the motion controlled by the triple junction kinetics to the boundary kinetics is observed. By this is meant that the triple junction along with the other structural defects can drag the boundary motion, or, conversely, and their role and properties should be taken into consideration in theories of grain growth. (C) 1998 Acta Metallurgica Inc. Published by Elsevier Science Ltd. Ali rights reserved.