EFFFECT OF CURRENT PULSE ON SUPERPLASTICITY AND FRACTURE BEHAVIOUR OF 2091 Al-Li ALLOY
脉冲电流对2091Al—Li合金超塑性及断裂行为的影响

Effects of current pulse on mechanical behaviors and fracture mechanism of 2091 Al-Li superplastically deformed at high strain rate have been investigated. Applying a direct current pulse makes the 2091 Al-Li alloy still with high stress-strain rate sensiitivity exponent and superplastic properties under superplastically deformed at high strain rate of 10~(-2)s~(-1). SEM observation showed that the fracture for 2091 Al-Li alloy, superplastically de- formed at high strain rate by applying current pulse, transforms from intergranular tear to typical superplastic failure, i. e., fracture by formation and coalescene of cavities at particles and boundaries.