The Brazilian mining company CBMM, which supplies approximately 80% of the world’s industrialized niobium products, is providing funding for a researcher at Saarland University for three years through the project ‘Niobium in Steel’. The aim of the research work is not only to achieve a more detailed understanding of the mechanisms within steel, but also to improve control of the steel production process itself.
Although Niobium (Nb) is used in comparatively small amounts in steel production, it plays an important role in high-strength, low alloy steels, as well as in applications in tools steels, wear and abrasion resistant steels, stainless steels and others.
Niobium accounts for only about one in every 10,000 atoms in steel. It’s therefore all the more surprising to see what a major effect these small concentrations have. The presence of niobium makes the steel tougher—meaning that it becomes more stretchable without losing its strength. Niobium also prevents steel from becoming brittle and breaking like porcelain at sub-zero temperatures.—Professor Frank Mücklich, Department of Functional Materials at Saarland University
This is particularly relevant in the case of oil and gas pipelines that have to operate at arctic temperatures. In the automotive industry, niobium acts as an alloying element in the steel used to make car body parts, so that the vehicle is able to absorb enough energy on impact to protect the passenger cabin in the event of a crash.
Mücklich’s research team specializes in performing spatial analyses of the internal structures of materials at different dimensional scales and has developed a number of three-dimensional methods for use in this field. Over the last few years, the researchers have been able to fine tune their techniques to produce a suite of closely aligned methods for the structural analysis of materials.
Using their 3D analytical techniques, the researchers in Saarbrücken are now in a position to map quantitatively the internal structure of steel and to identify the mechanisms that control specific required material properties.
We want to understand the internal structure of steel as precisely as possible and we want to know the role the niobium atoms play in the steel’s microstructure and how this changes over the course of the steel production process. Only then will we be in a position to design the internal structure of the steel for a particular technical application and the desired properties. We would then know, for example, how to use niobium in the most effective way to produce superior material properties and how we can reduce other costly alloying elements or expensive process steps by targeted employing of niobium.—Frank Mücklich
Professor Mücklich presented these precision 3D analytical techniques to a group of niobium researchers from around the world, who were invited last year to a workshop that was held on the Saarbrücken campus.