Page 31 - Best of 2019 English

The key to any insights gained are the so- called “phases” in the steel – specific sections of the material that are identical in terms of their composition, shape, density and other properties. The phases undergo transformation – due to the impact of temperature, for example – and occur in varied forms: the different phase types in steel. It is the number, quantity and orientation of these phases that determine the properties of the steel. In addition to desirable phases, there are also un- desirable phases that have a negative impact.
This is an area Dr. Mentz and her colleagues
are working on: “We calculate the phases that are created when we anneal a steel at temperature x for period y, or the annealing temperature required
to eliminate a phase or alter the properties of the steel”. All this is done using simulation tools,
many of which provide very specific insights. “Phase field modeling offers a very good match between simulation and experiment,” says Dr. Charles Stallybrass. In fact, FEM simulation for tube forming is so accurate that essentially no ex- periments are required to design the tools required for the process, for instance.
Despite these impressive results, mathematical modeling still has enormous development poten- tial. Dr. Ritterbach expects findings to be much better and more accurate in the future: “The next step will be to use simulations to make precise pre- dictions of how our products respond to further processing or to be able to foresee the properties of components made from our material.” In other words: SZMF is working on making the future of steel predictable.
Dr. Juliane Mentz studied process engineering in Berlin and obtained her doctorate in the field
of materials science at Forschungszentrum Jülich. She started at SZMF in 2007 and in 2016 became Head of the Materials Engi- neering Unit in Duisburg with its departments for corrosion, joining and heat technology and materials development
Dr. Charles Stallybrass
A native of Vienna,
Dr. Charles Stallybrass studied materials science at the University of Leoben in Austria and wrote his doctoral thesis at the Max Planck Institute for Iron Research. He joined SZMF in 2005 and has been in charge of the Materials Development Department since 2016
SZMF in Duisburg is home to one of the largest research hot rolling mills in Europe. Here, the experts are using a small slab to investigate how the properties of the steel change as it cools between rolling operations
STEEL IN FIGURES 31
Photos: Carsten Brand, SZMF