Stress Induced Grain Boundary Motion in Al bicrystals

Recent results of experimental research into stress induced grain boundary migration in aluminum bicrystals are briefly reviewed. Boundary migration under a shear stress was observed to be coupled to a lateral translation of the grains for any < 100 > tilt boundary in the entire misorientation range (0-90 degrees). Measurements of the temperature dependence of coupled boundary migration revealed that there is a specific misorientation dependence of migration activation parameters. Grain boundaries can act during their motion under the applied stress as sources of lattice dislocations that leads to the generation and growth of new grains in the boundary region. The rate of stress induced boundary migration decreases with increasing solute content in aluminum. Both the migration activation enthalpy and the pre-exponential mobility factor were found to increase with rising impurity concentration.