SLIP SYSTEMS AND DISLOCATION DISTRIBUTION IN α-PHASE OF SUPERPLASTICALLY DEFORMED Ti-6AI-4V ALLOY

The activated slip systems in the α-phase of the superplastically deformed Ti-6Al-4V alloywere analyzed by systematic operation method with TEM.The results show that thedominately activated slip systems in the α-phase are{01(?)0}〈2(?)0〉and{01(?)}2(?)0〉,The{0001}〈2(?)0〉system as well as the c+a dislocalions of b=1/3]〈11(?)3〉will be acti-vated when the deformation temperature is lowered.Large amounts of TEM observations in-dicate that the dislocations in the α-phase were mainly activated near the triple grain bounda-ry junctions,α/α grain boundaries and α/β interlaces.