New approach for plastic deformation behavior of GH4169 superalloy with in-situ electric-pulse current at 800 °C

The tensile tests were conducted to investigate the plastic deformation behavior of GH4169 alloy with in-situ electric-pulse current (EPC) at 800 °C, and mechanisms of EPC on plastic deformation during different stage were discussed. The results show that in-situ EPC induces the decreasing of flow stress and the improving of plasticity compared with that without EPC. The flow stress instantaneously increases/decreases without any delay with removing/recovering EPC during deformation. It is found that the thermal vibration of atoms enhances leading to decreasing of Peierls stress with in-situ EPC, which is the essential factor on flow stress decrease. Although, with in-situ EPC, the γ′′ phases are induced to precipitate and then grow up, resulting in changing dislocation motion mode with γ′′ phase.