Sustainable Steel Making

More than 1.85 billion tons of steel are produced every year, making it the most important alloy in terms of volume and impact. While steel is a sustainability enabler, through lightweight car parts, wind farms and magnets, its primary production is the opposite. Its reduction from oxides by use of fossil carbon carriers produces 2t CO₂/t of steel, qualifying it as the largest single cause of global warming.

This presentation is an introduction to the most important pending basic research questions associated with producing steel more sustainably, particularly with lower CO₂ emissions.

It opens a critical discussion on the question what the basic science topics behind green steel making are and which key research questions must be tackled primarily to re-invent a 3000-year-old industry within a few years. Also it is discussed which reduction methods are the most promising ones and which scientific bottleneck questions must be solved to make Green Steel become reality. Therefore, the presentation addresses some recent progress and open issues in understanding the key mechanisms of hydrogen-based direct reduction and hydrogen-based plasma reduction including topics such as the kinetics of the solid state and plasma-based reduction reactions, mass transport kinetics, nucleation during the multiple phase transformations, the oxide’s chemistry and microstructure, the roles of plasticity, damage and fracture associated with the phase transformation and mass transport phenomena occurring during and possible simulation approaches.