Over the past year, Taiyuan Iron and Steel Co., Ltd. (TISCO) has seen its duplex stainless steel plates emerge as a standout in the stainless steel industry, flourishing even amid a severe market downturn. These plates not only achieved growth against the odds, with annual settlements surpassing 100,000 tons for the first time in history, setting a new record and yielding significant benefits, but they also continually conquered critical technical challenges, achieving new breakthroughs in various aspects.
Duplex stainless steel is known for its low cost, high strength, and excellent corrosion resistance. Over time, it has developed into a series of products with varying alloy contents and performance levels, continuing to evolve towards economically viable, low-nickel and highly corrosion-resistant super duplex grades. In recent years, TISCO has conducted extensive R&D on economical duplex stainless steels, successfully developing a range of plates that meet the needs of petrochemical, shipbuilding, and seawater desalination sectors. In 2023, TISCO successfully trialed the production of the S32202 economical duplex stainless steel plates, flawlessly fulfilling a supply of 120 tons for a Qatar chemical storage tank project, filling a domestic gap. The 2304 economical wide-width duplex stainless steel cold plate passed customer site inspections and signed an exclusive supply technical agreement, marking its first entry into the chemical heat exchanger field. Addressing the specific requirements of a foreign cathode plate project, TISCO overcame the challenge of controlling the narrow range of surface roughness on economical duplex stainless steel cold plates, achieving a new breakthrough in the application fields of duplex stainless steel plates.
TISCO is also the first domestic company to produce super duplex stainless steel plates. With the official operation of the 4300mm hot rolling plate production line and associated technical expertise, 2023 saw new advancements in the development of super thick super duplex stainless steel plates. After extensive testing and adopting advanced rolling techniques, the research team overcame the challenge of controlling the uniformity of super thick plate structures, achieving mass production of super duplex stainless steel plates with a thickness of 115mm, which supports the domestication of materials for petrochemical, paper, and offshore platform projects.
As the outstanding advantages of duplex stainless steel continue to gain market recognition, new high-end application areas are emerging. In 2023, TISCO passed the certification for duplex stainless steel cold plates for submarine hoses by a renowned foreign company, becoming the only qualified supplier in China. Additionally, its hot-rolled duplex stainless steel plates received the Norsok M650 special materials license, an internationally recognized quality management system and product license, demonstrating TISCO’s strong capabilities in technology and quality assurance for duplex stainless steel plates.