Turning scrap into high-performance steel

Max Planck team participates in EU project exploring the influence of residual elements in recycled steel

At a glance:

• Project: NANO-S-MART: NANOengineering of Sustainable MARTensitic steels
• Budget: €3.08 million for four years
• Goal: Enable sustainable steel production using more recycled scrap
• Approach: Linking industrial processing, nanoscale analysis and materials design to understand how residual elements affect steel microstructure and performance

Steel production contributes to 5.7% of the greenhouse gas emissions in the European Union. A large share of those emissions is caused by the primary synthesis of iron from iron ore. Increasing the share of recycled scrap is therefore a key strategy for reducing emissions from the sector. However, till now increased use of scrap introduces residual elements such as copper, tin and phosphorus that accumulate in recycled steel and cannot easily be removed during processing. Even in small concentrations, they can influence the steel’s properties.

The European research project NANO-S-MART investigates how these residual elements influence the microstructure and performance of martensitic steels. By understanding their behaviour at the atomic scale, researchers of the Max Planck Institute for Sustainable Materials (MPI-SusMat) and scientists from several academic and industrial partners aim to enable high-quality steels that can be produced with a larger share of recycled materials and lower CO₂ emissions.

Seeing residual elements at the atomic scale

“A central question is how residual elements are distributed within martensitic steels, and what impact they have on performance. We employ atom probe tomography to visualise these elements in 3D at the atomic scale, providing critical insights that guide the development of steels compatible with low-CO₂, sustainable production methods”, explains Dr. Raymond Nutor, postdoctoral researcher at MPI-SusMat. The researchers focus on quenched-and-tempered martensitic steels, a class of high-strength steels widely used in automotive structures, construction and energy infrastructure. These applications require materials that combine strength, toughness and reliability.

A European effort to enable circular steel production

The NANO-S-MART project is funded with 3.08 million euros over four years by the European Union. It brings together experts from materials science and industrial processing. Partners include OCAS NV, Ghent University, Karlsruhe Institute of Technology, and the Max Planck Institute for Sustainable Materials, alongside the project coordinator CEIT Technology Centre.