Microstructures et Recristallisation
J. Phys. IV 05 (1995) C3-89-C3-106
High-Angle Grain Boundary Migration in Aluminium BicrystalsG. Gottstein1, D.A. Molodov1, U. Czubayko1 and L.S. Shvindlerman2
1 Institut für Metallkunde und Metallphysik, RWTH Aachen, D-52056 Aachen, Germany
2 Institute of Solid State Physics, Russian Academy of Science, Chernogolovka, Moscow distr., 142432 Russia
The measurement of grain boundary migration in pure Al bicrystals by X-ray continuous interface tracking is introduced. This method provides information on the mobility of specific grain boundaries without interfering with the process of migration. Moreover, the effect of hydrostatic pressure on grain boundary migration was investigated. Several topics of grain boundary motion relevant to microstructure and texture evolution by recrystallization and grain growth were addressed. It was found that the maximum growth rate misorientation changes with temperature from the exact ∑7 orientation relationship to a 40.50°<111> rotation. This behavior is of concern for recrystallization texture evolution. The effect of material purity on grain boundary migration is shown not to be confined to drag effects but also to involve changes of grain boundary structure. From the activation volume of grain boundary mobility it has to be concluded that at least <110> tilt boundaries move by cooperative motion (group mechanism) of atoms in the boundary.
© EDP Sciences 1995