Enhanced Bio-corrosion Resistance by Cu Alloying in a Micro-alloyed Pipeline Steel

摘要

On the composition base of commercial X65 grade pipeline steels,a Cu modified pipeline steel was designed to show improved resistance to microbially induced corrosion(MIC).The mechanical properties of the Cu-added steel and its corrosion behavior in a soil solution inoculated with sulfate-reducing bacteria(SRB)were investigated in this work.The results demonstrated that Cu-added steel exhibits a good combination of strength and toughness.Cu ions released from the Cu-added steel could effectively kill the SRB attaching on the steel surface,thus evidently decreased the pit depth and diameter of Cu-added steel.Furthermore,during the long-term immersion,the Cu-rich film formed by the enrichment of Cu in the corrosion product layer on the steel surface could also contribute to the improvement of the bio-corrosion resistance of Cu-added steel.