Aluminium makes chromium-nickel steels lighter, stronger and more corrosion-resistant
How can chromium-nickel steels be made lighter, stronger and, at the same time, more sustainable? A research project by the University of Kassel and the TU Bergakademie Freiberg is investigating the impact of the targeted addition of aluminium on the properties of steel – and how this could lead to a material of the future.
“Stainless steel – commonly referred to as ‘stainless’ – has become an integral part of our everyday lives, whether as cutlery in the kitchen, as a component in cars or in high-tech applications. The aim of my PhD research is to further develop the material so that it meets the increasing demands for sustainability and resource efficiency,” says welding engineer Steffen Scherbring, a research assistant and PhD student at Osnabrück University of Applied Sciences.
Why aluminium?
Whilst aluminium is usually only used in steel production for oxygen removal (deoxidation), this PhD research is investigating its use as a permanent alloying element. Initial results show that adding five per cent aluminium not only makes the steel lighter and stronger, but also more corrosion-resistant; it also has good weldability and improved wear resistance. Furthermore, scrap compatibility is improved – this refers to the ability to use a higher proportion of recycled material in steel production without compromising quality. This is a crucial factor for sustainable recycling processes.
Challenges in production
“Although these positive properties are already known, the use of aluminium in these quantities has hardly been tested to date,” says Scherbring. “The reason is that aluminium reacts very quickly on contact with oxygen – a risk that has so far been deemed too high in industrial steel production.” Processing is therefore currently being tested in various application projects in collaboration with industry partners. These include products that are subjected to heavy abrasion at high temperatures – for example, in waste-to-energy plants or in hydrogen production.
Source: Osnabrück University of Applied Sciences