22 Acoustic Emission Monitoring of Pitting Corrosion …
259
Fig. 22.3 AE characteristic parameters time history plot
energy are relatively small. As the reaction progressed, pitting gradually entered the
expansion phase. In the second stage (after 5632 s), the zirconium metal reacts with
the solution at the destruction of the oxide film to cause activation-passivation of the
galvanic cell reaction, the metal begins to dissolve, hydrogen bubbles continuously
evolve on the metal surface, and the electrochemical reaction begins to enter the
active state. As the metal dissolves, the number of hydrogen bubbles increases, and
the activity and hit of the corresponding AE signals also increase. The signal at this
259
Fig. 22.3 AE characteristic parameters time history plot
energy are relatively small. As the reaction progressed, pitting gradually entered the
expansion phase. In the second stage (after 5632 s), the zirconium metal reacts with
the solution at the destruction of the oxide film to cause activation-passivation of the
galvanic cell reaction, the metal begins to dissolve, hydrogen bubbles continuously
evolve on the metal surface, and the electrochemical reaction begins to enter the
active state. As the metal dissolves, the number of hydrogen bubbles increases, and
the activity and hit of the corresponding AE signals also increase. The signal at this