Celebrating a century of innovation: The evolution of duplex stainless steel at Avesta

As Outokumpu's Avesta site commemorates the 100th anniversary of its first stainless steel melt, we reflect on one of the site’s most groundbreaking accomplishments: the development of duplex stainless steel. This innovation is more than just a part of Avesta's legacy. Since its inception, it has represented a revolution in the global stainless steel industry.

Marie-Louise FalklandMarie Louise Falkland, Senior Technical Manager at Outokumpu, has been contributing to the ongoing development of duplex stainless steel for more than 35 years.

“Duplex stainless steel has been vital to our business for many years,” says Falkland, “and it has a huge potential to create even greater successes in the future, giving us even more reason to embrace and celebrate innovation.”


The birth and growth of duplex stainless steel

The journey of duplex stainless steel began in the 1930s when the first grades were developed. However, it was not until the late 20th century that duplex stainless steel gained widespread recognition and adoption. This was largely due to advancements in metallurgy and processing techniques, many of which were pioneered at Avesta site in Sweden. 

“In my production and R&D capacity, I’ve overseen many improvements to our quality and efficiency,” says Falkland. “As one of the world’s biggest producers of sustainable stainless steel, we have crucial leverage in the form of processes and knowledge that we’ve developed over the years, and we use those to deliver reliable products with consistency.”

The innovation of duplex stainless steel is a testament to Avesta's commitment to pushing the boundaries of what is possible. Over the years, the site has continually improved and expanded its duplex portfolio, leading to the development of high-performance grades that have significantly enhanced the material's versatility — and thereby risen to meet the evolving demands of various industries. A brief history of duplex grade innovation could be summarized like so:

The first duplex stainless steel grades were created in the 1930s
Modern grades were developed in the 1970s, greatly expanding the possibilities for adoption
In the late 80s and early 90s, the use of duplex increased rapidly along with the development of new grades
The first lean duplex grade was developed in 2002, making duplex stainless steel affordable for general use
Later, formable duplex grades were created for even more demanding applications

Each of these milestones is worth celebrating in its own right, having played a role in cementing Avesta’s legacy of innovation while also making the benefits of duplex stainless steel available to more and more customers, providing fuel for cross-industry growth and development.


Shaping industries through innovation

Duplex stainless steel is known for its exceptional strength and corrosion resistance, and was originally developed to address the limitations of traditional types of stainless steel. Combining the best properties of those types gives duplex stainless steel superior performance in many applications, and has revolutioned various sectors by enabling the manufacture of safer, more durable, and longer-lasting infrastructure, equipment, and components.

Its high strength-to-weight ratio makes it a preferred choice for applications where weight is a critical factor, and its resistance to pitting, corrosion, and cracking makes it especially useful in harsh environments and extreme conditions. Put together, these qualities make duplex stainless steel extremely versatile, allowing for its use across a wide range of industries, from chemicals and oil and gas to water management and food processing. Along with increasing demand for safe and sustainable development, the need for innovative materials like duplex stainless steel will only continue to grow.

Case Maastank Rotterdam

A Vision for the Future

As Avesta, the heart of Outokumpu’s Advanced Materials business line, celebrates the centenary of its first stainless steel melt, the site continues to be the home of forward-looking innovation, redefining standards and driving change in the stainless steel industry. The development of duplex stainless steel is not just a chapter in Avesta's and Outokumpu’s history, but a foundation for future advancements.

“Along with exploring new processes and applications, we also have the major task of educating customers, regulators, and other stakeholders,” says Falkland. “Today, many people still don’t know what this material can do for them, but we aim to change that.”

Simply put, the story of duplex stainless steel is a shining example of Outokumpu’s enduring mission to build a world that lasts forever, its pivotal role in shaping the stainless steel industry, and its vital commitment to innovation. As we celebrate 100 years of progress, we also look ahead to the next century of innovation, driven by the same spirit of excellence that has defined the Avesta site for the past hundred years.