Contribution of the flowing conditions to the galvanic corrosion of the copper/AISI 316L coupling in highly concentrated LiBr solutions

The galvanic corrosion of copper/AISI 316L stainless steel couples has been studied under different temperatures and flowing conditions in heavy LiBr brines. The mixed potential theory, zero-resistance ammeter and weight loss measurements were performed. Temperature and Reynolds number increase galvanic corrosion rates of copper. Statistical analysis by means of multilevel factorial design reveals that temperature greatly affects galvanic current densities. Additionally, the mixed potential theory suggests that thermogalvanic corrosion may occur when the materials of the pair work at different temperatures. The most important increase of current densities due to thermogalvanic effects takes place at high Reynolds numbers with the highest difference of temperature between copper/AISI 316L pairs and the anode operating at 25 °C. The results obtained with the different techniques are in good agreement.

► Copper and AISI 316L stainless steel galvanic corrosion was studied in LiBr brines.
► Temperature and Reynolds number increase copper corrosion due to galvanic effect.
► Temperature is the most significant effect on the galvanic corrosion.
► Mixed potential theory estimates that thermogalvanic corrosion might occur.
► Results obtained from polarization, ZRA and weight loss tests are in good agreement.