The abnormal fracture of a conductive pipe of outdoor high-voltage disconnector is analyzed by means of chemical analysis

metallographic examination

scanning electron microscopy and energy spectrum analysis. The results show that denudation of the conductive pipe due to humid environment and the existence of Cl-caused the fracture. During the corrosion process

pitting corrosion first took place on uneven part of oxide film at local rupture

then the pitting corrosion developed into intercrystalline corrosion

finally leading to the denudation under the synergistic effect of intercrystalline corrosion and internal stress.