TEM INVESTIGATION ON THE MECHANISM OF NEAR-CSL ALPHA GRAIN BOUNDARY SLIDING IN SUPERPLASTICALLY DEFORMED Ti-6Al-4V ALLOY
超塑性变形Ti-6Al-4V合金中接近重位点阵取向α晶界滑动机制的TEM研究

The near-coincidence grain boundaries of alpha phase insuperplastically deformed Ti-6Al-4V alloy were investigated with TEM.Itwas found that the image of grain boundary dislocations (GBD) in some ofthe boundaries became diffusive but still maintained linear characteristic.There exist local dissociation and combination of some GBD. New configu-rations were formed by the combination of GBD in the grain boundary re-gion which connects with the substructure of the crystal.Lattice dislocationswere emitted from the grain boundary ledge consisting of three boundaryfaces on which the GBD orientatel in different directions.