Effects of cyclic stress on the metastable pitting characteristic for 304 stainless steel under potentiostatic polarization

• Current transients of metastable pitting have been detected during cyclic loading.
• Peak stress below yield strength has little effect on metastable pitting behaviour.
• Peak stress above yield strength (PSAY) increases metastable pitting events.
• PSAY promotes the growth of large metastable pits.

The effects of the cyclic stress on the metastable pitting corrosion for 304 stainless steel have been investigated under potentiostatic polarization. The results show that cyclic stress with peak stress above yield strength (PSAY) can significantly increase the metastable pitting events and promote the growth of large pits, while those with peak stress below yield strength have no obvious effect. It also reveals that PSAY can decrease the stable pitting potential. These results indicate that cyclic plastic deformation plays more important role on the metastable pitting behaviour than cyclic elastic deformation.