Nanosecond pulsed laser-assisted modified copper surface structure: Enhanced surface microhardness and microbial corrosion resistance

Microbiologically influenced corrosion (MIC) is an unavoidable problem in several industries. Copper (Cu) and its alloys are widely used engineering materials. However, MIC of Cu remains a persistent chal-lenge to their performance and functional lifetime under aggressive environments. This study investi-gated nanosecond pulsed laser processing (LP), which may enhance the corrosion resistance of Cu. The microstructural evolution and corrosion behavior of LP-Cu in the presence of sulfate-reducing bacteria (SRB) were evaluated. Typical deformation-induced microstructural features of high-density dislocations were analyzed on the top surface of LP-Cu coupon. Electrochemical measurements suggested that LP-Cu coupons exhibited better corrosion resistance in SRB-inoculated solution compared with their original counterpart. The enhanced corrosion resistance by LP primarily resulted from the combined influences of compressive residual stress and work hardening in the surface. However, overlap percentage played a key role in improving corrosion resistance. LP produced optimal corrosion resistance at 50% overlap. There-fore, this study introduces a unique and an option for anticorrosion control in manufacturing processes and potentially implements it onto other materials to improve its microbial corrosion resistance through LP. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

This study investigates the microstructural evolution and corrosion behavior of copper (Cu) under the presence of sulfate-reducing bacteria (SRB) using nanosecond pulsed laser processing (LP). The results show that LP can enhance the corrosion resistance of Cu, primarily due to the combined influences of compressive residual stress and work hardening on the surface. The overlap percentage also plays a key role in improving corrosion resistance, with optimal performance achieved at 50% overlap.