GRAIN BOUNDARY MIGRATION IN RECRYSTALLIZED Mo FOILS IN THE PRESENCE OF Ni

Grain boundary migration was investigated in recrystallized Mo foils in the presence of Ni between 800-1400°C. Grain boundary migration is pronounced at high temperatures when a high amount of Ni is present at the surface of the foils. Grain boundaries develop into facets having nearly the same orientation relationship. After prolonged annealing grain boundaries migrate back. Microprobe analyses in the wake of migrating grain boundaries show Mo(Ni)-ss while in front of the grain boundaries no Ni was found. Experiments with Mo foils in the absence of Ni show no occurrence of grain boundary migration.