Corrosion performance of NV E690 steel and 316L stainless steel coating fabricated by underwater direct metal deposition

• Published in: Corrosion science Vol. 219; p. 111232
• Main Authors: Chen, Mingzhi, Yang, Kun, Wang, Zhandong, Zhao, Kai, Wu, Erke, Shi, Jinjie, Qi, Huan, Sun, Guifang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.07.2023
• Subjects: Low alloy steel; Macro-segregation; Metal coatings; Stainless steel; Underwater direct metal deposition; Metal coatings; Macro-segregation; Low alloy steel; Stainless steel; Underwater direct metal deposition
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2023.111232

The corrosion resistance of NV E690 steel and 316L stainless steel (SS316L) coatings fabricated by underwater laser direct metal deposition (UDMD) was investigated. The corrosion resistance of the as-deposited NV E690 was improved by coating SS316L layers. The dilution effect coupling with macro-segregations (peninsula, island, and banded zone) deteriorated the corrosion resistance by forming preferential dissolution and crevice-shaped corrosion when depositing monolayer SS316L coating. While the above-mentioned drawbacks were alleviated when depositing bilayer SS316L coatings, thereby leading to higher corrosion resistance by forming a compact passive film. •The Corrosion resistance of NV E690 steel was improved by coating SS316L in UDMD.•Macro-segregation and dilution occur on as-deposited when fusing dissimilar metals.•Macro-segregation and dilution weaken the corrosion resistance of monolayer SS316L.•Corrosion resistance order: bilayer SS316L > monolayer SS316L > NV E690 layer.