Shape of moving grain boundaries in Al-bicrystals

It is common knowledge that grain boundary migration determines microstruct ure evolution and thus, affects the properties of polycrystals. The princip al parameter which controls the motion of a grain boundary is the grain bou ndary mobility. In practically all relevant cases the motion of a straight grain boundary is the exception rather than the rule. That is why the shape of a moving grain boundary is of interest, and it will be shown that the g rain boundary shape is a sourer of new, interesting and useful findings con cerning grain boundary motion, in particular for the interaction of a movin g grain boundary with mobile particles. The experimentally derived shape of a grain boundary "quarter-loop" (Masteller and Bauer, Recrystallization of Metallic Materials, Riederer Verlag, Stuttgart, 1978) in Al-bicrystals of different purity was compared with theoretical calculations in the Lucke-De tert approximation (Lucke and Detert, Acta metall., 1957, 5, 628). (C) 1999 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reser ved.