Electrochemical and localized corrosion behavior of 316 L SS/copper/316 L SS sandwich composite in chloride-containing environment

Electrochemical and localized corrosion behavior of a 316 L SS/copper/316 L SS composite in 0.5 wt. % NaCl solution was investigated from cross-sectional and plane directions by electrochemical measurements and high -resolution microscopic examination. The galvanic coupling accelerated the dissolution at the internal surface and pitting attack at the external surface of the 316 L layer. Polarization up to 1 V/SCE resulted in formation of a corrosion product layer (ca. 992 nm) composed of metal oxides/hydroxides on top of the passive film, which consisted of a Fe2O3-rich outer layer (3.3 nm) and a Cr2O3-rich inner layer (4.1 nm). The copper corrosion was quite uniform.Data availability statement: The raw/processed data required to reproduce these findings cannot be shared at this time as the data also forms part of an ongoing study.

Automated summary

In this study, the electrochemical and localized corrosion behavior of a 316L SS/copper/316L SS composite in a 0.5 wt. % NaCl solution was investigated using electrochemical measurements and high-resolution microscopic examination. Galvanic coupling accelerated the dissolution at the internal surface and pitting attack at the external surface of the 316L layer. Polarization up to 1 V/SCE resulted in the formation of a corrosion product layer composed of metal oxides/hydroxides on top of the passive film.