Lean Duplex Steel - a better alternative 12 January 2022

Wilhelm Modersohn GmbH & Co KG, manufacturer of industrial components and fastening systems for concrete and masonry, is focusing its attention on the price development of stainless, acid and heat resistant steels...

For some time now, Modersohn has been focusing on Lean Duplex steels, which are less volatile in terms of price. These are also currently cheaper and, due to their basic strength, which is at least twice as high as standard austenites, significantly more economical than austenites, which are comparable in terms of corrosion technology. The explanation lies in the lower alloying proportions of the expensive components, such as nickel and molybdenum, and in the increased proportion of chromium and nitrogen. According to the stainless steel expert, this makes the Lean Duplex steels a clear alternative to the standard A4 and A2 austenites in almost all common areas of application.

Further advantages over the standard austenites are higher fatigue strength; no chloride and hydrogen induced stress corrosion cracking up to 50°C; less risk of cold welding when bolting under load; good resistance at higher temperatures; i.e. not the typical chi or sigma phase embrittlement; as well as lower coefficient of thermal expansion with the same thermal transmittance of Lambda 15.

For many years, Modersohn has had an extensive stock of Lean Duplex steels, especially for sheet. Since the beginning of this year, the standard for "Mechanische Verbindungselemente" (mechanical fasteners) DIN EN ISO 3506 has been published in a revised version. With this internationally valid manufacturing and application basis for screws, nuts, washers, threaded rods, etc., more and more standard parts are coming onto the market as stock items. This means that the strength Class 100 is then often also available, with which Modersohn engineers can once again optimise the customer's product due to the better design possibilities.

Claire Aldridge Deputy Editor t: +44 (0) 1727 743 889

Having spent a decade in the fastener industry experiencing every facet – from steel mills, fastener manufacturers, wholesalers, distributors, as well as machinery builders and plating + coating companies, Claire has developed an in-depth knowledge of all things fasteners.

Alongside visiting numerous companies, exhibitions and conferences around the world, Claire has also interviewed high profile figures – focusing on key topics impacting the sector and making sure readers stay up to date with the latest developments within the industry.