There is a fast-growing need for a new generation of marine and offshore structures to support applications such as offshore wind and aquaculture, and marine-related infrastructure, including coastal protection.
The common factor in all these structures is the need for reliability and a long life, potentially 35 years or more. However, the usual approach of using carbon steel with a protective coating is a far from perfect solution. This is because it needs frequent maintenance. And in demanding offshore and marine environments, maintenance operations are complex and often associated with high costs.
Stainless steel, specifically duplex grades, offers a competitive alternative to coated carbon steel since its corrosion resistance and strength helps create lightweight, durable structures that require little to no maintenance.
However, while switching to duplex grades offers significant theoretical advantages, the lack of practical real-world experience in the offshore industry has been a major brake on their widespread adoption.
To bridge this experience gap, Outokumpu’s R&D team conducted field tests in the North Sea to evaluate the performance of high-strength duplex stainless steels under real marine conditions. This program has yielded practical data on how different duplex grades perform across various corrosion zones.
The information gathered is now available to support informed material selection that enables optimized grade choices for structures exposed to distinct marine environments and service conditions.
Overall, our findings show that duplex stainless steels provide a robust alternative to carbon steel solutions in offshore applications.