Newsportal - Ruhr-Universität Bochum

The way metals behave when plastically deformed depends heavily on how defects in the crystal lattice interact with each other. Professor Markus Stricker from Ruhr University Bochum, Germany, understands these so-called dislocations as networks and intends to analyze their behaviour using simulations. He’s been awarded a Starting Grant from the European Research Council ERC for this project. Starting in September 2024, “DISCO-DATA: Hard work, plastic flow: a data-centric approach to dislocation-based plasticity” will be funded for five years with 1.5 million euros.

Why less stress than expected is needed to deform a metal

Almost all the things we interact with daily contain metal components, and most of them have been manufactured into their final shape by plastic deformation. Industrial forming for the production of these objects is largely based on empirical values, such as how much stress is required to form a product from certain components and to a certain thickness. “Almost 100 years ago, we realized that the theoretical stress required for this purpose – i.e. force per surface area – was 100 to 1,000 times greater than the actual stress required,” says Markus Stricker. “This is due to defects in the crystal lattice of the metals that occur in lines, so-called dislocations.”

These dislocations are already well understood at the atomistic scale. On a larger scale, however, they interact in a complex way. For example, the interaction between dislocations is partly to blame for the fact that a metal becomes increasingly difficult to deform further with increasing deformation – an effect known as work hardening. “Previous models that attempt to describe this behavior don’t work very well yet,” says Markus Stricker. “Basically, the dislocation behavior underlying these effects is not really understood yet.”

He wants to use his ERC grant to investigate the interaction of dislocations for the first time by simulating them and explicitly representing them as networks using mathematical methods from graph theory. Using many simulations of different networks, he plans to create abstract networks and analyze their behavior during deformation. In the final step, he will then go back to the physical model.